Re: SWTPC 6800

[Brent Hilpert]

On 2016-Aug-04, at 11:46 PM, Brad H wrote:
> Dave
> Yes.. I tried 7 bits.. different parity settings, speeds etc.  Couldn't quite 
> nail it down.  In every tutorial online for the 6800 being used with PC 
> terminal, they go 8 N 1.. nobody mentions specifically if you are supposed to 
> use hardware or xo/off or nothing though.  So that's another thing.  I'm also 
> confused because some docs mention baud rate settings for the cpu board?
> I'm also not sure if bad RAM or bad TTL etc could be contributing to just 
> throwing out random junk too.



(Disclaimer: All my SWTP-6800 stuff is packed away at the moment, I'm going 
strictly from memory here.)


Flow control shouldn't be an issue.
This was an early simple (and slow) system, there was no active flow control 
(leaving aside the reader-run control for the TTY PTR).
What speed are you running at? I'd suggest starting out at a lower speed 
(300-1200).

Do you get a consistent response each time you hit the RESET button on the 
SWTP-6800?
The monitor pumps out a single prompt character at reset.
If you always get one character but the wrong character (or couple) after reset 
it could be a simple terminal protocol mismatch error, as you are pursuing.
If it's inconsistent, it may be a deeper problem.
If you have a DSO, you could sample the RS-232 output to the terminal and 
decode it to confirm the framing and bit rate are as you intend.


Random questions  / things to check:

1.  The MP-S is in the correct I/O slot for SWTBUG to find it for the console 
device?
(The SWTP-6800 backplane decodes the I/O addresses to particular slots.)


2.  IIRC, MIKBUG only knows how to work the MP-C interface for the console, 
while SWTBUG can do both MP-C & MP-S.
The proper ROM is present and the CPU board switches are configured correctly 
for SWTBUG?
Alternatively, you might consider trying the MP-C rather than the MP-S, 
although it's another set of hardware config jumpers to sort out.
(The MP-C was the original console interface as specified by Moto for MIKBUG, 
the MP-S came later.)


3.  IIRC, both BUG monitors require some RAM up at $Exxx or $Fxxx for the 
monitor stack (that 6810 RAM).
I don't think only having RAM down at $ will suffice.
The idea with the 6800 generally was system stuff (including the BUG monitors) 
was up at the top of mem, while low mem was freely available to the user.
(One of the world-view diffs between the 6800 and Z80.)

RE: SWTPC 6800

[Dave Wade]

> -Original Message-
> From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Brad H
> Sent: 05 August 2016 07:46
> To: General Discussion: On-Topic and Off-Topic Posts
> 
> Subject: RE: SWTPC 6800
> 
> 
> 
> Yes.. I tried 7 bits.. different parity settings, speeds etc.  Couldn't quite 
> nail it
> down.  In every tutorial online for the 6800 being used with PC terminal, they
> go 8 N 1.. nobody mentions specifically if you are supposed to use hardware
> or xo/off or nothing though.  So that's another thing.  I'm also confused
> because some docs mention baud rate settings for the cpu board?
> I'm also not sure if bad RAM or bad TTL etc could be contributing to just
> throwing out random junk too.
> 

If the data received is inconstant then bad RAM is a likely cause, ROM usually 
fails consistanly.

but as with all problem solving, Conan Doyle had it right when he said
"after eliminating the impossible, whatever is left, however improbable, must 
be the solution"

Dave
> 
> Sent from my Samsung device
> 
>  Original message 
> From: Dave Wade 
> Date: 2016-08-04  11:33 PM  (GMT-08:00)
> To: "'General Discussion: On-Topic and Off-Topic Posts'"
> 
> Subject: RE: SWTPC 6800
> 
> "Random Stuff" on serial ports can be a speed, data-bits, or even parity mis-
> match.
> I assume you have tried tweaking these?
> 
> Dave
> 
> > -Original Message-
> > From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Brad
> > H
> > Sent: 05 August 2016 06:58
> > To: 'General Discussion: On-Topic and Off-Topic Posts'
> > 
> > Subject: RE: SWTPC 6800
> >
> > I think this 6800 is live but I am being dogged by my inabilities when
> > it
> comes
> > to cabling.  I'm going to purchase a 'proper' db25 female connector
> > and
> the
> > molex pins for the MP-S connector and solder it up.  I tried sort of
> > using jumper wires to make it go.  When I turn the 6800 on, the PC
> > terminal I'm using reacts by producing single or strings of random
> characters.
> > According to the SWTPC 'system checkout' stuff, if I get anything at
> > all showing up on the terminal it usually means the 6800 is alive.
> > Based on
> the
> > notes written on the MP-S, I'm confident I have the correct baud rate
> > and
> bit
> > (8) and parity (1) settings, but alas, doesn't seem to work.  When I
> > ran
> into
> > this sort of thing with MSI 6800 it turned out the baud rate switch on
> > the serial card wasn't correct, despite factory labelling.  That might
> > be the
> case
> > here but not really sure how to sort it.
> >
> > -Original Message-
> > From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Paul
> Birkel
> > Sent: Thursday, August 4, 2016 12:29 PM
> > To: 'General Discussion: On-Topic and Off-Topic Posts'
> > 
> > Subject: RE: SWTPC 6800
> >
> 

RE: DEC Transistor assortment on Ebay

[tony duell]

> Interesting.  When looking at this I tripped over another DEC related item:
> 
> http://www.ebay.com/itm/DEC-DIGITAL-EQUIPMENT-CORPORATION-REEL-GO-NOGO-GAUGE/112082166031
> 
> I'm not sure what you'd use it for unless you were manufacturing DECtape
>  reels, but it certainly is interesting.  You could make one yourself, if you
>  have a lathe and the ability to hold tight tolerances.  One of the photos 
> actually shows the dimensions as written on the gauge.

Which suggests the spec is 2.5" +/- 5 thou (or thereabouts).

-tony

Re: DEC Transistor assortment on Ebay

[Paul Koning]

> On Aug 4, 2016, at 4:49 PM, Wayne Sudol  wrote:
> 
> Just spyed this on Ebay -  a box of DEC Transistors for sale.
> Might be useful to have if you like to repair DEC boards.
> 
> http://www.ebay.com/itm/DEC-DIGITAL-EQUIPMENT-CORPORATION-TRANSISTOR-ASSORTMENT-NOS-/112082168459?hash=item1a189e2a8b:g:zaEAAOSwbsBXotpF

Interesting.  When looking at this I tripped over another DEC related item:

http://www.ebay.com/itm/DEC-DIGITAL-EQUIPMENT-CORPORATION-REEL-GO-NOGO-GAUGE/112082166031

I'm not sure what you'd use it for unless you were manufacturing DECtape reels, 
but it certainly is interesting.  You could make one yourself, if you have a 
lathe and the ability to hold tight tolerances.  One of the photos actually 
shows the dimensions as written on the gauge.

paul

Re: DECtape reel gauge

[Paul Koning]

> On Aug 5, 2016, at 10:43 AM, tony duell  wrote:
> 
> 
>> Interesting.  When looking at this I tripped over another DEC related item:
>> 
>> http://www.ebay.com/itm/DEC-DIGITAL-EQUIPMENT-CORPORATION-REEL-GO-NOGO-GAUGE/112082166031
>> 
>> I'm not sure what you'd use it for unless you were manufacturing DECtape
>> reels, but it certainly is interesting.  You could make one yourself, if you
>> have a lathe and the ability to hold tight tolerances.  One of the photos 
>> actually shows the dimensions as written on the gauge.
> 
> Which suggests the spec is 2.5" +/- 5 thou (or thereabouts).

Yes, that's what those numbers imply.  It sounds plausible, given the springy 
hub used on DECtape.

I remember once or twice having to use a piece of punch card as a shim to keep 
a reel from coming off.  Not clear if wear was involved or an out of spec part 
that slipped through.

paul

RE: SWTPC 6800

[Fred Cisin]

but as with all problem solving, Conan Doyle had it right when he said 
"after eliminating the impossible, whatever is left, however improbable, 
must be the solution"


That quote is often horribly abused.  Diagnosis by elimination 
is inherently faulty.  Beginners, and "experts", will often 
use it to justify ridiculous premises, "because I eliminated everything 
else", while not having truly eliminated some of the most basic 
possibilities.  "It must be the carburetor, because everything else is 
new" usually meant that they had not gapped the points properly, or had 
the wrong firing order.


37? years ago, it took me 3 weeks to get ink on paper with a serial 
printing terminal and a TRS80, because I made stupid assumptions because I 
thought that I had eliminated . . .
and didn't even realize that there was a bad connection between the serial 
interface and the rest of the Expansion Interface.



Why do you think that you have the right baud rate?
It might be 9600, but if it was expecting a printing terminal, then it 
might be 300, 150, 134.5, 110, 75


In spite of "standardization" (everybody has a unique one of their own), 
sometimes you run into some handshaking using signals besides DSR, DTR, 
RTS, CTS. Such as CD (8), CD2 (12)!, RI(22)

"misuse of the standard"?  absolutely.
(using db25 pinout - BTW, a DE9 is not a DB9.  A real DB9 consists of a DB 
shell with 1 thru 8 and 20)



It can be frustrating.  There is at least one documented fatality from the 
frustration of serial cabling.   Guy took a printer and computer to store 
to get it cabled; after 6 weeks without success, he shot the tech.  Joe 
Campbell was sure that was an urban legend, so he tracked down the case, 
and mentioned it in one of his books.



I don't intend to ever do it again; I'm getting rid of my ARC Data Tek 
9600 DTS-1.



--
Grumpy Ol' Fred ci...@xenosoft.com

Re: SWTPC 6800

[Chris Elmquist]

On Thursday (08/04/2016 at 11:46PM -0700), Brad H wrote:
> 
> 
> Yes.. I tried 7 bits.. different parity settings, speeds etc.  Couldn't quite 
> nail it down.  In every tutorial online for the 6800 being used with PC 
> terminal, they go 8 N 1.. nobody mentions specifically if you are supposed to 
> use hardware or xo/off or nothing though.  So that's another thing.  I'm also 
> confused because some docs mention baud rate settings for the cpu board?
> I'm also not sure if bad RAM or bad TTL etc could be contributing to just 
> throwing out random junk too.

On SS-50, the baudrate clocks are sourced from the CPU board onto approx
5 pins on the backplane.  Originally, the top speed was 1200 baud and the
MP-S and other cards would be jumpered to whichever clock (and therefore
pin on the backplane) was the desired rate for that port.

Over time, people wanted the ports to run at higher speeds and so would
make a change on the CPU board (cut and jump, flip a switch, depending
on design) to repurpose a backplane clock line from its original less
desireable rate to a faster one.  For example, 150 baud was seldom used
and might get repurposed to a 9600 baud clock.

So, you need to know something about the CPU board's design in order to
know what clock rates get routed onto which backplane baud clock signals
and then you need to know which backplane baud clock signal the MP-S
card is connected to for its baud clock.

These were almost always 16X clocks too, so if you scope the backplane
signals, the rates you see should be 16 times what the baud rate is.

Chris

>  Original message 
> From: Dave Wade  
> Date: 2016-08-04  11:33 PM  (GMT-08:00) 
> To: "'General Discussion: On-Topic and Off-Topic Posts'" 
>  
> Subject: RE: SWTPC 6800 
> 
> "Random Stuff" on serial ports can be a speed, data-bits, or even parity
> mis-match. 
> I assume you have tried tweaking these?
> 
> Dave
> 
> > -Original Message-
> > From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Brad H
> > Sent: 05 August 2016 06:58
> > To: 'General Discussion: On-Topic and Off-Topic Posts'
> > 
> > Subject: RE: SWTPC 6800
> > 
> > I think this 6800 is live but I am being dogged by my inabilities when it
> comes
> > to cabling.  I'm going to purchase a 'proper' db25 female connector and
> the
> > molex pins for the MP-S connector and solder it up.  I tried sort of using
> > jumper wires to make it go.  When I turn the 6800 on, the PC terminal I'm
> > using reacts by producing single or strings of random characters.
> > According to the SWTPC 'system checkout' stuff, if I get anything at all
> > showing up on the terminal it usually means the 6800 is alive.  Based on
> the
> > notes written on the MP-S, I'm confident I have the correct baud rate and
> bit
> > (8) and parity (1) settings, but alas, doesn't seem to work.  When I ran
> into
> > this sort of thing with MSI 6800 it turned out the baud rate switch on the
> > serial card wasn't correct, despite factory labelling.  That might be the
> case
> > here but not really sure how to sort it.
> > 
> > -Original Message-
> > From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Paul
> Birkel
> > Sent: Thursday, August 4, 2016 12:29 PM
> > To: 'General Discussion: On-Topic and Off-Topic Posts'
> > 
> > Subject: RE: SWTPC 6800
> > 
> 
> 

-- 
Chris Elmquist

Re: VCF West - going?

[Corey Cohen]

Well come look for me and say HI.  I'll be there. 

corey cohen
uǝɥoɔ ʎǝɹoɔ

On Aug 4, 2016, at 12:25 PM, Ali  wrote:

>> I am heading to VCF West after a stop over in San Fran today...I am
>> looking forward to meeting up with everyone.  I will be there all day
>> Friday as a set-up volunteer, Sat and Sunday morning.  I was at the
>> last VCF before it was called "West" ... it's been too long.
> 
> I am going to be there both days and look forward to meeting people In Real 
> Life (TM). So should the list members get special badges or something so 
> people can know who is who? Or *GASP* are we going to have to be personable 
> and talk to each other! :D
> 
> -Ali
> 

Re: VCF West - going?

[Josh Dersch]

On Thu, Aug 4, 2016 at 12:25 PM, Ali  wrote:

> > I am heading to VCF West after a stop over in San Fran today...I am
> > looking forward to meeting up with everyone.  I will be there all day
> > Friday as a set-up volunteer, Sat and Sunday morning.  I was at the
> > last VCF before it was called "West" ... it's been too long.
>
> I am going to be there both days and look forward to meeting people In
> Real Life (TM). So should the list members get special badges or something
> so people can know who is who? Or *GASP* are we going to have to be
> personable and talk to each other! :D
>
> -Ali
>
>
I'll be there co-running the Living Computer Museum's exhibit.  Stop by and
say hi!

- Josh

RE: SWTPC 6800

[Brad H]

I'll answer by number here:

1) MP-S is in Slot 1, per instructions.

2) This MP-A board has been modified for both SWTBUG and Flex.  I noted the
traces that were cut and matched to both configs.

3) Ah, this may be part of my problem.  I don't quite understand memory
addressing yet.  The instructions said you needed RAM at A000 if the 6810
chip was disabled (which it appears to be, the correct trace is cut).  My
machine has 4 RAM boards.  2 are MPM, 2 are 16K DRC boards.  For whatever
reason, the DRC boards are config-ed to be first (-3FFF) and second
(4000-7FFF).   Trying to strip the machine down and have as little RAM as I
could get away with, I just installed the single board at -3FFF.  These
boards are (thank god) socketed, so I have some means of testing and
removing RAM.  The MP-M boards are not socketed, so I don't want to mess
with those until I have to.  I could config the second DRC board for the
$Exxx-$Fxxx and shove it in there.

-Original Message-
From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Brent
Hilpert
Sent: Friday, August 5, 2016 12:37 AM
To: General Discussion: On-Topic and Off-Topic Posts 
Subject: Re: SWTPC 6800

On 2016-Aug-04, at 11:46 PM, Brad H wrote:
> Dave
> Yes.. I tried 7 bits.. different parity settings, speeds etc.  Couldn't
quite nail it down.  In every tutorial online for the 6800 being used with
PC terminal, they go 8 N 1.. nobody mentions specifically if you are
supposed to use hardware or xo/off or nothing though.  So that's another
thing.  I'm also confused because some docs mention baud rate settings for
the cpu board?
> I'm also not sure if bad RAM or bad TTL etc could be contributing to just
throwing out random junk too.



(Disclaimer: All my SWTP-6800 stuff is packed away at the moment, I'm going
strictly from memory here.)


Flow control shouldn't be an issue.
This was an early simple (and slow) system, there was no active flow control
(leaving aside the reader-run control for the TTY PTR).
What speed are you running at? I'd suggest starting out at a lower speed
(300-1200).

Do you get a consistent response each time you hit the RESET button on the
SWTP-6800?
The monitor pumps out a single prompt character at reset.
If you always get one character but the wrong character (or couple) after
reset it could be a simple terminal protocol mismatch error, as you are
pursuing.
If it's inconsistent, it may be a deeper problem.
If you have a DSO, you could sample the RS-232 output to the terminal and
decode it to confirm the framing and bit rate are as you intend.


Random questions  / things to check:

1.  The MP-S is in the correct I/O slot for SWTBUG to find it for the
console device?
(The SWTP-6800 backplane decodes the I/O addresses to particular slots.)


2.  IIRC, MIKBUG only knows how to work the MP-C interface for the console,
while SWTBUG can do both MP-C & MP-S.
The proper ROM is present and the CPU board switches are configured
correctly for SWTBUG?
Alternatively, you might consider trying the MP-C rather than the MP-S,
although it's another set of hardware config jumpers to sort out.
(The MP-C was the original console interface as specified by Moto for
MIKBUG, the MP-S came later.)


3.  IIRC, both BUG monitors require some RAM up at $Exxx or $Fxxx for the
monitor stack (that 6810 RAM).
I don't think only having RAM down at $ will suffice.
The idea with the 6800 generally was system stuff (including the BUG
monitors) was up at the top of mem, while low mem was freely available to
the user.
(One of the world-view diffs between the 6800 and Z80.)

RE: SWTPC 6800

[Brad H]

RAM could certainly be an issue.  I had *tons* of bad RAM dogging me with my 
Digital Group Z80.  That took two weeks of testing to get through it.  I might 
just test out all this RAM in the DRC boards first and see if I can get away 
with just using those rather than bringing the soldered MP-M boards into the 
mix right now.

-Original Message-
From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Dave Wade
Sent: Friday, August 5, 2016 2:42 AM
To: 'General Discussion: On-Topic and Off-Topic Posts' 
Subject: RE: SWTPC 6800

> -Original Message-
> From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Brad 
> H
> Sent: 05 August 2016 07:46
> To: General Discussion: On-Topic and Off-Topic Posts 
> 
> Subject: RE: SWTPC 6800
> 
> 
> 
> Yes.. I tried 7 bits.. different parity settings, speeds etc.  
> Couldn't quite nail it down.  In every tutorial online for the 6800 
> being used with PC terminal, they go 8 N 1.. nobody mentions 
> specifically if you are supposed to use hardware or xo/off or nothing 
> though.  So that's another thing.  I'm also confused because some docs 
> mention baud rate settings for the cpu board?
> I'm also not sure if bad RAM or bad TTL etc could be contributing to 
> just throwing out random junk too.
> 

If the data received is inconstant then bad RAM is a likely cause, ROM usually 
fails consistanly.

but as with all problem solving, Conan Doyle had it right when he said "after 
eliminating the impossible, whatever is left, however improbable, must be the 
solution"

Dave
> 
> Sent from my Samsung device
> 
>  Original message 
> From: Dave Wade 
> Date: 2016-08-04  11:33 PM  (GMT-08:00)
> To: "'General Discussion: On-Topic and Off-Topic Posts'"
> 
> Subject: RE: SWTPC 6800
> 
> "Random Stuff" on serial ports can be a speed, data-bits, or even 
> parity mis- match.
> I assume you have tried tweaking these?
> 
> Dave
> 
> > -Original Message-
> > From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of 
> > Brad H
> > Sent: 05 August 2016 06:58
> > To: 'General Discussion: On-Topic and Off-Topic Posts'
> > 
> > Subject: RE: SWTPC 6800
> >
> > I think this 6800 is live but I am being dogged by my inabilities 
> > when it
> comes
> > to cabling.  I'm going to purchase a 'proper' db25 female connector 
> > and
> the
> > molex pins for the MP-S connector and solder it up.  I tried sort of 
> > using jumper wires to make it go.  When I turn the 6800 on, the PC 
> > terminal I'm using reacts by producing single or strings of random
> characters.
> > According to the SWTPC 'system checkout' stuff, if I get anything at 
> > all showing up on the terminal it usually means the 6800 is alive.
> > Based on
> the
> > notes written on the MP-S, I'm confident I have the correct baud 
> > rate and
> bit
> > (8) and parity (1) settings, but alas, doesn't seem to work.  When I 
> > ran
> into
> > this sort of thing with MSI 6800 it turned out the baud rate switch 
> > on the serial card wasn't correct, despite factory labelling.  That 
> > might be the
> case
> > here but not really sure how to sort it.
> >
> > -Original Message-
> > From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of 
> > Paul
> Birkel
> > Sent: Thursday, August 4, 2016 12:29 PM
> > To: 'General Discussion: On-Topic and Off-Topic Posts'
> > 
> > Subject: RE: SWTPC 6800
> >
> 

Re: VCF West - going?

[william degnan]

I am here now, will be around all day helping set up.  I have not been to
the CHM since the last VCF...The space for the event looks good, tables are
out and waiting for exhibitors.

On Fri, Aug 5, 2016 at 12:07 PM, Josh Dersch  wrote:

> On Thu, Aug 4, 2016 at 12:25 PM, Ali  wrote:
>
> > > I am heading to VCF West after a stop over in San Fran today...I am
> > > looking forward to meeting up with everyone.  I will be there all day
> > > Friday as a set-up volunteer, Sat and Sunday morning.  I was at the
> > > last VCF before it was called "West" ... it's been too long.
> >
> > I am going to be there both days and look forward to meeting people In
> > Real Life (TM). So should the list members get special badges or
> something
> > so people can know who is who? Or *GASP* are we going to have to be
> > personable and talk to each other! :D
> >
> > -Ali
> >
> >
> I'll be there co-running the Living Computer Museum's exhibit.  Stop by and
> say hi!
>
> - Josh
>



-- 
@ BillDeg:
Web: vintagecomputer.net
Twitter: @billdeg 
Youtube: @billdeg 
Unauthorized Bio 

RE: SWTPC 6800

[Brad H]

I don't think I have the right baud rate at all... as I mentioned, my MSI
6800 has a very well labelled serial card and I set it to whatever baud rate
I was going for, set my terminal up and it wouldn't work.  It was only by
accident that I discovered if I set the terminal to 9600 baud it worked.
Some of the other switches worked at the speeds labelled but I think 1200 or
whatever was 9600.  So I wouldn't be surprised at all if this thing was
modified beyond.  I have the MP-S, and I have the previous owner's
handwritten sticker with the baud rates for each of the 5 DIP switches.. and
so I've got it set at what should be 300, but I have tried other baud rates
up and down the line without success so far.  Going up just produces longer
strings of random characters.  Going down produces less.

I am using a 25 pin femaile to 9 pin female null modem cable.  The 9 pin
goes into my old Thinkpad 380 and the 25 pin I have jumpered.  I followed
the guide here:  http://www.swtpc.com/mholley/HiTerm/MPS_to_DB25.pdf

Now, I don't have a DB25 female connector I could solder wires to.  So what
I did was, where required to loop pin 4 to 5, I just took some jumper wire,
and went from pin 4 to 5 on the female 25 pin (at the computer end), 6 to
20, 6 to 8, and so on.  You can get two jumper wire pins into a single shaft
so the connections are all good. But maybe it doesn't work that way, I know
null modem cables are a bit different.  In any event, wired as such, the
terminal got nothing from the computer at all.

In the event, I ended up reducing to having the MP-S set up per the
instructions, and then just had the TX RX and ground connected from the card
to the female connector.  With that setup, I get a response, albeit garbled.
I'm certain cabling is an issue here.  I get a bit dyslexic with pins and
understanding how things change on a cable like a null modem.

-Original Message-
From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Fred Cisin
Sent: Friday, August 5, 2016 8:52 AM
To: General Discussion: On-Topic and Off-Topic Posts 
Subject: RE: SWTPC 6800

> but as with all problem solving, Conan Doyle had it right when he said 
> "after eliminating the impossible, whatever is left, however 
> improbable, must be the solution"

That quote is often horribly abused.  Diagnosis by elimination is inherently
faulty.  Beginners, and "experts", will often use it to justify ridiculous
premises, "because I eliminated everything else", while not having truly
eliminated some of the most basic possibilities.  "It must be the
carburetor, because everything else is new" usually meant that they had not
gapped the points properly, or had the wrong firing order.

37? years ago, it took me 3 weeks to get ink on paper with a serial printing
terminal and a TRS80, because I made stupid assumptions because I thought
that I had eliminated . . .
and didn't even realize that there was a bad connection between the serial
interface and the rest of the Expansion Interface.


Why do you think that you have the right baud rate?
It might be 9600, but if it was expecting a printing terminal, then it might
be 300, 150, 134.5, 110, 75

In spite of "standardization" (everybody has a unique one of their own),
sometimes you run into some handshaking using signals besides DSR, DTR, 
RTS, CTS. Such as CD (8), CD2 (12)!, RI(22)
"misuse of the standard"?  absolutely.
(using db25 pinout - BTW, a DE9 is not a DB9.  A real DB9 consists of a DB
shell with 1 thru 8 and 20)


It can be frustrating.  There is at least one documented fatality from the 
frustration of serial cabling.   Guy took a printer and computer to store 
to get it cabled; after 6 weeks without success, he shot the tech.  Joe
Campbell was sure that was an urban legend, so he tracked down the case, and
mentioned it in one of his books.


I don't intend to ever do it again; I'm getting rid of my ARC Data Tek
9600 DTS-1.


--
Grumpy Ol' Fred ci...@xenosoft.com

RE: SWTPC 6800

[Brad H]

So here's a video I made of the terminal connected to my SWTPC.  I set
hyperterminal to 8, N, 1.  As you can see there's no action with the reset
button, but there is a random character on power up.

https://www.youtube.com/watch?v=dvT_KYyRVWo

I then tried 7 N 1 (that's how my CT1024 terminal is set up).  This time I
got more consistent characters.  If I hit reset, there is also a response.

https://www.youtube.com/watch?v=ZYitTyUUxFg

Re: VCF West - going?

[Ian Finder]

I'll be there. Flying down from Seattle after work with an Amiga 4000 060
and a GRiD in my carry-on.
I wanted to bring a Symbolics machine, but they happen to be quite heavy. ;)

On Fri, Aug 5, 2016 at 10:01 AM, william degnan 
wrote:

> I am here now, will be around all day helping set up.  I have not been to
> the CHM since the last VCF...The space for the event looks good, tables are
> out and waiting for exhibitors.
>
> On Fri, Aug 5, 2016 at 12:07 PM, Josh Dersch  wrote:
>
> > On Thu, Aug 4, 2016 at 12:25 PM, Ali  wrote:
> >
> > > > I am heading to VCF West after a stop over in San Fran today...I am
> > > > looking forward to meeting up with everyone.  I will be there all day
> > > > Friday as a set-up volunteer, Sat and Sunday morning.  I was at the
> > > > last VCF before it was called "West" ... it's been too long.
> > >
> > > I am going to be there both days and look forward to meeting people In
> > > Real Life (TM). So should the list members get special badges or
> > something
> > > so people can know who is who? Or *GASP* are we going to have to be
> > > personable and talk to each other! :D
> > >
> > > -Ali
> > >
> > >
> > I'll be there co-running the Living Computer Museum's exhibit.  Stop by
> and
> > say hi!
> >
> > - Josh
> >
>
>
>
> --
> @ BillDeg:
> Web: vintagecomputer.net
> Twitter: @billdeg 
> Youtube: @billdeg 
> Unauthorized Bio 
>



-- 
   Ian Finder
   (206) 395-MIPS
   ian.fin...@gmail.com

Re: SWTPC 6800

[william degnan]

Here is a picture/thread about the wiring of the MP-S and cable comparing
Teletype with RS232.
http://vintagecomputer.net/browse_thread.cfm?id=174


Here is a thread I made, plus a special file I created for loading TSC BASIC
http://vintagecomputer.net/browse_thread.cfm?id=416

hope this helps.

Re: SWTPC 6800

[Brent Hilpert]

On 2016-Aug-05, at 9:55 AM, Brad H wrote:
> 
> 3) Ah, this may be part of my problem.  I don't quite understand memory
> addressing yet.  The instructions said you needed RAM at A000 if the 6810
> chip was disabled (which it appears to be, the correct trace is cut).  My
> machine has 4 RAM boards.  2 are MPM, 2 are 16K DRC boards.  For whatever
> reason, the DRC boards are config-ed to be first (-3FFF) and second
> (4000-7FFF).   Trying to strip the machine down and have as little RAM as I
> could get away with, I just installed the single board at -3FFF.  These
> boards are (thank god) socketed, so I have some means of testing and
> removing RAM.  The MP-M boards are not socketed, so I don't want to mess
> with those until I have to.  I could config the second DRC board for the
> $Exxx-$Fxxx and shove it in there.

Don't take my word on the specific address, I should have just said you need 
some RAM in high mem.
The 6810 was there to fulfill that need of RAM for the xxxBUG monitor.
You might reenable it, or config a RAM board to cover that range (A000? to ?).
But if you use a RAM board you have to config it so it doesn't extend up into 
(overlap) the ROM and IO address space.

(I have a memory map for this on another machine not set up at this time).

(For purposes of exercising the xxxBUG monitors you don't need memory down at 
$.)

Re: SWTPC 6800

[Brad H]

Okay thanks.  I gues where I'm getting confused is Michael Holley's guide to 
new 6800 users says because of the 6810 being cut you want RAM at $A000.. what 
you're suggesting sounds like the opposite?  Maybe I'd better reread those 
instructions.


Sent from my Samsung device

 Original message 
From: Brent Hilpert  
Date: 2016-08-05  10:52 AM  (GMT-08:00) 
To: "General Discussion: On-Topic and Off-Topic Posts"  
Subject: Re: SWTPC 6800 

On 2016-Aug-05, at 9:55 AM, Brad H wrote:
> 
> 3) Ah, this may be part of my problem.  I don't quite understand memory
> addressing yet.  The instructions said you needed RAM at A000 if the 6810
> chip was disabled (which it appears to be, the correct trace is cut).  My
> machine has 4 RAM boards.  2 are MPM, 2 are 16K DRC boards.  For whatever
> reason, the DRC boards are config-ed to be first (-3FFF) and second
> (4000-7FFF).   Trying to strip the machine down and have as little RAM as I
> could get away with, I just installed the single board at -3FFF.  These
> boards are (thank god) socketed, so I have some means of testing and
> removing RAM.  The MP-M boards are not socketed, so I don't want to mess
> with those until I have to.  I could config the second DRC board for the
> $Exxx-$Fxxx and shove it in there.

Don't take my word on the specific address, I should have just said you need 
some RAM in high mem.
The 6810 was there to fulfill that need of RAM for the xxxBUG monitor.
You might reenable it, or config a RAM board to cover that range (A000? to ?).
But if you use a RAM board you have to config it so it doesn't extend up into 
(overlap) the ROM and IO address space.

(I have a memory map for this on another machine not set up at this time).

(For purposes of exercising the xxxBUG monitors you don't need memory down at 
$.)

RE: SWTPC 6800

[Fred Cisin]

On Fri, 5 Aug 2016, Brad H wrote:

I then tried 7 N 1 (that's how my CT1024 terminal is set up).  This time I
got more consistent characters.  If I hit reset, there is also a response.


If and when you get consistent characters, no matter how wrong, then it's 
time to look at the bit patterns of what you get V what you expect  (is 
anybody around who knows?)
Since, obviously, if consistent, then it might be right except for one or 
more bits stuck on or stuck off.


Yes, it is frustrating.

RE: SWTPC 6800

[Brad H]

Yeah to be honest.. I'm not sure I'm the biggest serial terminal computer fan.  
I find them way harder to diagnose than computers with video cards.  But, the 
SWTPC is an iconic system.. so I'll just keep muddling until I figure it out.


Sent from my Samsung device

 Original message 
From: Fred Cisin  
Date: 2016-08-05  11:25 AM  (GMT-08:00) 
To: "General Discussion: On-Topic and Off-Topic Posts"  
Subject: RE: SWTPC 6800 

On Fri, 5 Aug 2016, Brad H wrote:
> I then tried 7 N 1 (that's how my CT1024 terminal is set up).  This time I
> got more consistent characters.  If I hit reset, there is also a response.

If and when you get consistent characters, no matter how wrong, then it's 
time to look at the bit patterns of what you get V what you expect  (is 
anybody around who knows?)
Since, obviously, if consistent, then it might be right except for one or 
more bits stuck on or stuck off.

Yes, it is frustrating.

Re: SWTPC 6800

[Chris Elmquist]

On Friday (08/05/2016 at 11:23AM -0700), Brad H wrote:
> 
> 
> Okay thanks.  I gues where I'm getting confused is Michael Holley's guide to 
> new 6800 users says because of the 6810 being cut you want RAM at $A000.. 
> what you're suggesting sounds like the opposite?  Maybe I'd better reread 
> those instructions.

MIKBUG and SWTBUG need the RAM at $A000 not $.  RAM at $A000 was
the original MEK6800-D1 reference design for which MIKBUG was invented
and the MP-A is likely derived.

As an aside, I have what I think is a kinda rare EXORBUS to SS-50
adapter that SWTPC may have made during development of the machine so
that an MEK6800-D1 could be used as the CPU board on SS-50 bus.  It is
an interposer with 86-pin EXORBUS socket on the top and (5) 10-pin MOLEX
on the bottom which mate to one of the SS-50 50-pin backplane locations.

It has SWTPC logo on it so I don't think it was a third-party deal.

Chris

>  Original message 
> From: Brent Hilpert  
> Date: 2016-08-05  10:52 AM  (GMT-08:00) 
> To: "General Discussion: On-Topic and Off-Topic Posts" 
>  
> Subject: Re: SWTPC 6800 
> 
> On 2016-Aug-05, at 9:55 AM, Brad H wrote:
> > 
> > 3) Ah, this may be part of my problem.  I don't quite understand memory
> > addressing yet.  The instructions said you needed RAM at A000 if the 6810
> > chip was disabled (which it appears to be, the correct trace is cut).  My
> > machine has 4 RAM boards.  2 are MPM, 2 are 16K DRC boards.  For whatever
> > reason, the DRC boards are config-ed to be first (-3FFF) and second
> > (4000-7FFF).   Trying to strip the machine down and have as little RAM as I
> > could get away with, I just installed the single board at -3FFF.  These
> > boards are (thank god) socketed, so I have some means of testing and
> > removing RAM.  The MP-M boards are not socketed, so I don't want to mess
> > with those until I have to.  I could config the second DRC board for the
> > $Exxx-$Fxxx and shove it in there.
> 
> Don't take my word on the specific address, I should have just said you need 
> some RAM in high mem.
> The 6810 was there to fulfill that need of RAM for the xxxBUG monitor.
> You might reenable it, or config a RAM board to cover that range (A000? to ?).
> But if you use a RAM board you have to config it so it doesn't extend up into 
> (overlap) the ROM and IO address space.
> 
> (I have a memory map for this on another machine not set up at this time).
> 
> (For purposes of exercising the xxxBUG monitors you don't need memory down at 
> $.)
> 

-- 
Chris Elmquist

RE: SWTPC 6800

[tony duell]

> > I then tried 7 N 1 (that's how my CT1024 terminal is set up).  This time I
> > got more consistent characters.  If I hit reset, there is also a response.
> 
> If and when you get consistent characters, no matter how wrong, then it's
> time to look at the bit patterns of what you get V what you expect  (is
> anybody around who knows?)
> Since, obviously, if consistent, then it might be right except for one or
> more bits stuck on or stuck off.
> 
> Yes, it is frustrating.

Am I the only person who rarely, if ever, has RS232 problems?

I don't guess, I don't try things until it works. I make measurements
and figure out how it must work. 

In this case, I would guess the serial chip is either a dumb UART (one
of those 40 pin ones) or a 6850. Both have the advantage (here) of
needing an external baud rate clock. So, stick a 'scope, frequency counter,
LogicDart, whatever you use on the Transmit clock pin. Measure the
frequency and remember that almost all serial chips need a 16* baud
clock. So divide what you measure by 16, set that baud rate.

Set 1 stop bit on the terminal. If the system sends 2, it won't matter.
It's asynchronous, it's just an extra bit delay between characters.

Try 8 bits, no parity. Most machines sent 8 bits, the high bit might
be a parity bit. If some characters get through, others are corrupted
into graphics-type things (extended character set) then work out if the
high bit is being set on odd or even parity, and re-set the terminal to
7 data bits and the appropriate parity bit.

If all else fails, stick a logic analyser on the Tx Data pin of the UART,
trigger on the falling edge, and grab the bitstream as it comes out
of the UART. See if you can make sense of it. 

-tony

RE: SWTPC 6800

[Fred Cisin]

On Fri, 5 Aug 2016, Brad H wrote:

I'm certain cabling is an issue here.  I get a bit dyslexic with pins and
understanding how things change on a cable like a null modem.


OK, I don't know what your level of knowledge is on it.  Mine is NOT very 
high, so please don't be offended if I tell grandma how to suck eggs.



I would have hoped that, expecting a terminal, it would be wired as DCE 
(Data Communications Equipment), and plug straight through to a DTE (Data 
Terminal Equipment).


However, a PC is NOT expecting a terminal to be connected to it, and is 
wired DTE!  (PC is a terminal expecting to connect to a modem, not 
something to connect a terminal to.)


Therefore, ideally, the PC should connect straight through, with only
software issues of baud-rate, parity, bits, stop bits, and software 
handshaking.  That obviously is not the case, and rarely is.

Oh, wouldn't it be great if it worked that easily.

A null modem is for connecting two DTE terminals to each other.
It connects the transmit of one side to the receive of the other, and 
often numerous hand-shaking signals, which are NOT really standardized.

(RTS,CTS,DSR,DTR,CD)
For example, if you want to connect a PC (DTE) to a printing terminal to 
use that as a printer, you need to cross TX and RX, and then mess with 
handshaking enough to get the PC to send characters when the printer is 
ready, and stop sending when the printer is not ready.  Sometimes, that is 
done by connecting handshake lines so that the PC ALWAYS sees the printer 
as ready, and then just send the characters slowly enough that the printer 
can keep up.  (typically 300 baud for daisy wheel, 150 or less for 
selectric).  Sometimes stop bits can help, if things are close.


They are usually wired symmetrically, but that doesn't always work.
With full handshaking, that crosses
TX and RX
DTR and DSR
RTS and CTS

With partial handshaking, that may be
TX and RX
RTS and CTS
DTR and CD+DSR

sometimes:
TX and RX
DTR and DSR
RTS and CTS+CD

It is kinda essential to get or make a breakout box.
1) to be able to try different interconnects
2) to have LEDs showing you the state of the lines.

Joe Campbell's "The RS232 Solution" is at a level that I can follow.
'course, there's always LUCK.  I had an assistant, who, the very first 
time that he saw a serial printer, he reached into one of my bins of 
random cables; and it worked!

Re: SWTPC 6800

[Chris Elmquist]

On Friday (08/05/2016 at 06:50PM +), tony duell wrote:
> 
> Am I the only person who rarely, if ever, has RS232 problems?

No.  ;-)

-- 
Chris Elmquist

RE: SWTPC 6800

[tony duell]

>
> > Am I the only person who rarely, if ever, has RS232 problems?
> 
> No.  ;-)

I should have been more specific and added something like 
'even though I have plenty of classic computers with RS232 ports,
serial terminals, serial printers, and so on' :-)

-tony

Re: SWTPC 6800

[Chris Elmquist]

On Friday (08/05/2016 at 07:05PM +), tony duell wrote:
> >
> > > Am I the only person who rarely, if ever, has RS232 problems?
> > 
> > No.  ;-)
> 
> I should have been more specific and added something like 
> 'even though I have plenty of classic computers with RS232 ports,
> serial terminals, serial printers, and so on' :-)

I have more trouble with USB...  because all of the "issues" end up in
a software space that's not easily explored or fixed.

-- 
Chris Elmquist

Re: SWTPC 6800

[Fred Cisin]

On Friday (08/05/2016 at 06:50PM +), tony duell wrote:

Am I the only person who rarely, if ever, has RS232 problems?

On Fri, 5 Aug 2016, Chris Elmquist wrote:

No.  ;-)


OK, that's TWO.
The rest of us are still struggling with our ignorance.


Your explanation of baud-rate and bit numbere/parity was excellent, and 
would have really helpe me 37 years ago.
But, it would not have solved the hassles that I had then with 
determining partial handshake connections, nor trying to connect an 
external serial Votrax to a TRS80 Model2.  It wanted a connection on pin 
22 (ring indicator)!  I did it for the Radio Shack Computer Store, in 
their store.  In return for which, they gave me a copy of the Model2 
Technical Reference.  Yes, I hung onto "Technical Reference" books even 
for machines that I did not own.   I had access to more information than 
I understood.



--
Grumpy Ol' Fred ci...@xenosoft.com

Re: SWTPC 6800

[Wayne Sudol]

Hi Brad. Troubleshooting baud rate and parity issues can be very
frustrating. Might i suggest using an simple rs-232c breakout box to see
what signals are being produced on the port?  Check if the txd and rxd
blink when you hit the carriage return on your pc? Then you'll know if the
garbage seen is really a baud issue or just some noise that's put on the
line when you power up the swtpc.

On Fri, Aug 5, 2016 at 10:04 AM, Brad H  wrote:

> I don't think I have the right baud rate at all... as I mentioned, my MSI
> 6800 has a very well labelled serial card and I set it to whatever baud
> rate
> I was going for, set my terminal up and it wouldn't work.  It was only by
> accident that I discovered if I set the terminal to 9600 baud it worked.
> Some of the other switches worked at the speeds labelled but I think 1200
> or
> whatever was 9600.  So I wouldn't be surprised at all if this thing was
> modified beyond.  I have the MP-S, and I have the previous owner's
> handwritten sticker with the baud rates for each of the 5 DIP switches..
> and
> so I've got it set at what should be 300, but I have tried other baud rates
> up and down the line without success so far.  Going up just produces longer
> strings of random characters.  Going down produces less.
>
> I am using a 25 pin femaile to 9 pin female null modem cable.  The 9 pin
> goes into my old Thinkpad 380 and the 25 pin I have jumpered.  I followed
> the guide here:  http://www.swtpc.com/mholley/HiTerm/MPS_to_DB25.pdf
>
> Now, I don't have a DB25 female connector I could solder wires to.  So what
> I did was, where required to loop pin 4 to 5, I just took some jumper wire,
> and went from pin 4 to 5 on the female 25 pin (at the computer end), 6 to
> 20, 6 to 8, and so on.  You can get two jumper wire pins into a single
> shaft
> so the connections are all good. But maybe it doesn't work that way, I know
> null modem cables are a bit different.  In any event, wired as such, the
> terminal got nothing from the computer at all.
>
> In the event, I ended up reducing to having the MP-S set up per the
> instructions, and then just had the TX RX and ground connected from the
> card
> to the female connector.  With that setup, I get a response, albeit
> garbled.
> I'm certain cabling is an issue here.  I get a bit dyslexic with pins and
> understanding how things change on a cable like a null modem.
>
> -Original Message-
> From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Fred
> Cisin
> Sent: Friday, August 5, 2016 8:52 AM
> To: General Discussion: On-Topic and Off-Topic Posts <
> cctalk@classiccmp.org>
> Subject: RE: SWTPC 6800
>
> > but as with all problem solving, Conan Doyle had it right when he said
> > "after eliminating the impossible, whatever is left, however
> > improbable, must be the solution"
>
> That quote is often horribly abused.  Diagnosis by elimination is
> inherently
> faulty.  Beginners, and "experts", will often use it to justify ridiculous
> premises, "because I eliminated everything else", while not having truly
> eliminated some of the most basic possibilities.  "It must be the
> carburetor, because everything else is new" usually meant that they had not
> gapped the points properly, or had the wrong firing order.
>
> 37? years ago, it took me 3 weeks to get ink on paper with a serial
> printing
> terminal and a TRS80, because I made stupid assumptions because I thought
> that I had eliminated . . .
> and didn't even realize that there was a bad connection between the serial
> interface and the rest of the Expansion Interface.
>
>
> Why do you think that you have the right baud rate?
> It might be 9600, but if it was expecting a printing terminal, then it
> might
> be 300, 150, 134.5, 110, 75
>
> In spite of "standardization" (everybody has a unique one of their own),
> sometimes you run into some handshaking using signals besides DSR, DTR,
> RTS, CTS. Such as CD (8), CD2 (12)!, RI(22)
> "misuse of the standard"?  absolutely.
> (using db25 pinout - BTW, a DE9 is not a DB9.  A real DB9 consists of a DB
> shell with 1 thru 8 and 20)
>
>
> It can be frustrating.  There is at least one documented fatality from the
> frustration of serial cabling.   Guy took a printer and computer to store
> to get it cabled; after 6 weeks without success, he shot the tech.  Joe
> Campbell was sure that was an urban legend, so he tracked down the case,
> and
> mentioned it in one of his books.
>
>
> I don't intend to ever do it again; I'm getting rid of my ARC Data Tek
> 9600 DTS-1.
>
>
> --
> Grumpy Ol' Fred ci...@xenosoft.com
>
>

Re: SWTPC 6800

[Pete Lancashire]

My 2cents

Some of this may have been mentioned. Your going to need an oscilloscope,
and a scope probe with a good ground. Your 'scope probe should
be less than 15 pF. Anymore and the probe will start to filter out any high
frequency noise.

Is the supplies output grounded ?, If so that point is where you put your
ground clip. Since this will be 90% of what you will find, I won't go into
non grounded DC sources.

Check what the output of your DC supplies looks like. The actual voltage
and the amount of ripple (60/120 or 50/100 Hz noise) and other noise
and what the ground at the exit of the supply looks like. Yes the ground.
If your happy with no ground noise you can use that point for your
ground clip.

Lets assume you have boards that plug in to a backplane. With all the
boards installed what do the supplies and again the ground(s) look like ?

Have an extender ? For each board, look at where the boards ground passes
to the backplane, if that point looks good, then you can move your
probes ground to that location. Now do the same thing, if just a 2 layer
board look at the ground pins on various devices, starting with the 'big'
chips,
then bus drivers, etc. Basically the devices that swing a lot of current.

Unique for memory boards. do the same for every device. Is the ground and
power pin clean ? One reason to look at every device is there maybe
a defective decoupling cap. Or sadly not enough of them. If the board is
only 2 layers and there is not a cap for each and every memory chip the fun
beings.

To keep things short, if the supply lines do not looks clean, your going to
be wasting a lot of time. What is clean, there is not short answer,
think about < 50-100 mV on every chip, specially memory devices.

Even the 'big boys' that should have know better designed and shipped a lot
of hardware that totally sucked.








On Fri, Aug 5, 2016 at 9:56 AM, Brad H 
wrote:

> RAM could certainly be an issue.  I had *tons* of bad RAM dogging me with
> my Digital Group Z80.  That took two weeks of testing to get through it.  I
> might just test out all this RAM in the DRC boards first and see if I can
> get away with just using those rather than bringing the soldered MP-M
> boards into the mix right now.
>
> -Original Message-
> From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Dave Wade
> Sent: Friday, August 5, 2016 2:42 AM
> To: 'General Discussion: On-Topic and Off-Topic Posts' <
> cctalk@classiccmp.org>
> Subject: RE: SWTPC 6800
>
> > -Original Message-
> > From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Brad
> > H
> > Sent: 05 August 2016 07:46
> > To: General Discussion: On-Topic and Off-Topic Posts
> > 
> > Subject: RE: SWTPC 6800
> >
> >
> >
> > Yes.. I tried 7 bits.. different parity settings, speeds etc.
> > Couldn't quite nail it down.  In every tutorial online for the 6800
> > being used with PC terminal, they go 8 N 1.. nobody mentions
> > specifically if you are supposed to use hardware or xo/off or nothing
> > though.  So that's another thing.  I'm also confused because some docs
> mention baud rate settings for the cpu board?
> > I'm also not sure if bad RAM or bad TTL etc could be contributing to
> > just throwing out random junk too.
> >
>
> If the data received is inconstant then bad RAM is a likely cause, ROM
> usually fails consistanly.
>
> but as with all problem solving, Conan Doyle had it right when he said
> "after eliminating the impossible, whatever is left, however improbable,
> must be the solution"
>
> Dave
> >
> > Sent from my Samsung device
> >
> >  Original message 
> > From: Dave Wade 
> > Date: 2016-08-04  11:33 PM  (GMT-08:00)
> > To: "'General Discussion: On-Topic and Off-Topic Posts'"
> > 
> > Subject: RE: SWTPC 6800
> >
> > "Random Stuff" on serial ports can be a speed, data-bits, or even
> > parity mis- match.
> > I assume you have tried tweaking these?
> >
> > Dave
> >
> > > -Original Message-
> > > From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of
> > > Brad H
> > > Sent: 05 August 2016 06:58
> > > To: 'General Discussion: On-Topic and Off-Topic Posts'
> > > 
> > > Subject: RE: SWTPC 6800
> > >
> > > I think this 6800 is live but I am being dogged by my inabilities
> > > when it
> > comes
> > > to cabling.  I'm going to purchase a 'proper' db25 female connector
> > > and
> > the
> > > molex pins for the MP-S connector and solder it up.  I tried sort of
> > > using jumper wires to make it go.  When I turn the 6800 on, the PC
> > > terminal I'm using reacts by producing single or strings of random
> > characters.
> > > According to the SWTPC 'system checkout' stuff, if I get anything at
> > > all showing up on the terminal it usually means the 6800 is alive.
> > > Based on
> > the
> > > notes written on the MP-S, I'm confident I have the correct baud
> > > rate and
> > bit
> > > (8) and parity (1) settings, but alas, doesn't seem to work.  When I
> > > ran
> > into
> > > this sort of t

MicroVax II update

[Douglas Taylor]

Progress on getting the MVII up and running:

I ordered the SCSI2SD adapter and it has come in, the plan is to use it 
as the system disk on the MVII.


The hobbyist VMS PAKS have arrived and I was able to download the VMS 
7.3 iso, not sure what I can do with it since I think it must be burned 
to a 512 byte sector CD.


I asked if the PAKS were good for older versions of VMS, like 5.5, and 
was told yes they were.  We'll see about that.


The Hobbyist VMS CD I had for VMS 7.2 was found and I was able to get 
the old Toshiba CD drive to work on the MV 4000 using a CQD 223A.  How 
can I create an image of these CD's on the VAX 4000 that I could use in 
an emulator?


I wasn't able to get the UC07 to see the CDROM because of a bad SCSI 
cable, I had hoped to format the SCSI2SD using the UC07.


Is it possible to use the SCSI2SD on a microPDP-11 under RT-11? I ask 
because of the disk size limit under RT-11.


Doug

Re: MicroVax II update

[derschjo]

> On Aug 5, 2016, at 1:42 PM, Douglas Taylor  wrote:
> 
> Progress on getting the MVII up and running:
> 
> I ordered the SCSI2SD adapter and it has come in, the plan is to use it as 
> the system disk on the MVII.
> 
> The hobbyist VMS PAKS have arrived and I was able to download the VMS 7.3 
> iso, not sure what I can do with it since I think it must be burned to a 512 
> byte sector CD.

Burn it to a CD.  Shouldn't be anything complex here.

> 
> I asked if the PAKS were good for older versions of VMS, like 5.5, and was 
> told yes they were.  We'll see about that.
> 
> The Hobbyist VMS CD I had for VMS 7.2 was found and I was able to get the old 
> Toshiba CD drive to work on the MV 4000 using a CQD 223A.  How can I create 
> an image of these CD's on the VAX 4000 that I could use in an emulator?
> 
> I wasn't able to get the UC07 to see the CDROM because of a bad SCSI cable, I 
> had hoped to format the SCSI2SD using the UC07

Keep in mind that the SCSI2SD can pretend to be a CD-ROM, and can emulate up to 
4 SCSI devices at one go.  No need to futz with a real drive if you don't want 
to...

Josh


> 
> Is it possible to use the SCSI2SD on a microPDP-11 under RT-11? I ask because 
> of the disk size limit under RT-11.
> 
> Doug
> 

RE: SWTPC 6800

[Brad H]

I think I will have to figure out how to do that.  Additionally I have one of 
those PC based oscilloscopes on the way.  I don't know how to use them 100% but 
I'm about to learn I guess. :)

I have one more question for you guys -- I have a few CT-1024 terminals and 
would really like this system to work with one of those.  However, all of the 
CTs are quite delicate and are set I think for 7, E, 2 @ 110 baud via soldered 
jumpers.  I'm a bit reluctant to try pulling them apart to get in there and fix 
that.  Is there a way to change the parity, etc settings on the SWTPC to match 
the terminal?  Is it necessary?

-Original Message-
From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Wayne Sudol
Sent: Friday, August 5, 2016 10:35 AM
To: General Discussion: On-Topic and Off-Topic Posts 
Subject: Re: SWTPC 6800

Hi Brad. Troubleshooting baud rate and parity issues can be very frustrating. 
Might i suggest using an simple rs-232c breakout box to see what signals are 
being produced on the port?  Check if the txd and rxd blink when you hit the 
carriage return on your pc? Then you'll know if the garbage seen is really a 
baud issue or just some noise that's put on the line when you power up the 
swtpc.

On Fri, Aug 5, 2016 at 10:04 AM, Brad H  wrote:

> I don't think I have the right baud rate at all... as I mentioned, my 
> MSI
> 6800 has a very well labelled serial card and I set it to whatever 
> baud rate I was going for, set my terminal up and it wouldn't work.  
> It was only by accident that I discovered if I set the terminal to 
> 9600 baud it worked.
> Some of the other switches worked at the speeds labelled but I think 
> 1200 or whatever was 9600.  So I wouldn't be surprised at all if this 
> thing was modified beyond.  I have the MP-S, and I have the previous 
> owner's handwritten sticker with the baud rates for each of the 5 DIP 
> switches..
> and
> so I've got it set at what should be 300, but I have tried other baud 
> rates up and down the line without success so far.  Going up just 
> produces longer strings of random characters.  Going down produces less.
>
> I am using a 25 pin femaile to 9 pin female null modem cable.  The 9 
> pin goes into my old Thinkpad 380 and the 25 pin I have jumpered.  I 
> followed the guide here:  
> http://www.swtpc.com/mholley/HiTerm/MPS_to_DB25.pdf
>
> Now, I don't have a DB25 female connector I could solder wires to.  So 
> what I did was, where required to loop pin 4 to 5, I just took some 
> jumper wire, and went from pin 4 to 5 on the female 25 pin (at the 
> computer end), 6 to 20, 6 to 8, and so on.  You can get two jumper 
> wire pins into a single shaft so the connections are all good. But 
> maybe it doesn't work that way, I know null modem cables are a bit 
> different.  In any event, wired as such, the terminal got nothing from 
> the computer at all.
>
> In the event, I ended up reducing to having the MP-S set up per the 
> instructions, and then just had the TX RX and ground connected from 
> the card to the female connector.  With that setup, I get a response, 
> albeit garbled.
> I'm certain cabling is an issue here.  I get a bit dyslexic with pins 
> and understanding how things change on a cable like a null modem.
>
> -Original Message-
> From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Fred 
> Cisin
> Sent: Friday, August 5, 2016 8:52 AM
> To: General Discussion: On-Topic and Off-Topic Posts < 
> cctalk@classiccmp.org>
> Subject: RE: SWTPC 6800
>
> > but as with all problem solving, Conan Doyle had it right when he 
> > said "after eliminating the impossible, whatever is left, however 
> > improbable, must be the solution"
>
> That quote is often horribly abused.  Diagnosis by elimination is 
> inherently faulty.  Beginners, and "experts", will often use it to 
> justify ridiculous premises, "because I eliminated everything else", 
> while not having truly eliminated some of the most basic 
> possibilities.  "It must be the carburetor, because everything else is 
> new" usually meant that they had not gapped the points properly, or 
> had the wrong firing order.
>
> 37? years ago, it took me 3 weeks to get ink on paper with a serial 
> printing terminal and a TRS80, because I made stupid assumptions 
> because I thought that I had eliminated . . .
> and didn't even realize that there was a bad connection between the 
> serial interface and the rest of the Expansion Interface.
>
>
> Why do you think that you have the right baud rate?
> It might be 9600, but if it was expecting a printing terminal, then it 
> might be 300, 150, 134.5, 110, 75
>
> In spite of "standardization" (everybody has a unique one of their 
> own), sometimes you run into some handshaking using signals besides DSR, DTR,
> RTS, CTS. Such as CD (8), CD2 (12)!, RI(22)
> "misuse of the standard"?  absolutely.
> (using db25 pinout - BTW, a DE9 is not a DB9.  A real DB9 consists of 
> a DB shell with 1 thru 8 and 20)
>
>
> It can

Re: VCF West - going?

[Curious Marc]

I'll be there with some of my HP equipment. On my way there soon.
Marc

Sent from my iPad

> On Aug 5, 2016, at 10:08 AM, Ian Finder  wrote:
> 
> I'll be there. Flying down from Seattle after work with an Amiga 4000 060
> and a GRiD in my carry-on.
> I wanted to bring a Symbolics machine, but they happen to be quite heavy. ;)
> 
> On Fri, Aug 5, 2016 at 10:01 AM, william degnan 
> wrote:
> 
>> I am here now, will be around all day helping set up.  I have not been to
>> the CHM since the last VCF...The space for the event looks good, tables are
>> out and waiting for exhibitors.
>> 
>>> On Fri, Aug 5, 2016 at 12:07 PM, Josh Dersch  wrote:
>>> 
>>> On Thu, Aug 4, 2016 at 12:25 PM, Ali  wrote:
>>> 
> I am heading to VCF West after a stop over in San Fran today...I am
> looking forward to meeting up with everyone.  I will be there all day
> Friday as a set-up volunteer, Sat and Sunday morning.  I was at the
> last VCF before it was called "West" ... it's been too long.
 
 I am going to be there both days and look forward to meeting people In
 Real Life (TM). So should the list members get special badges or
>>> something
 so people can know who is who? Or *GASP* are we going to have to be
 personable and talk to each other! :D
 
 -Ali
>>> I'll be there co-running the Living Computer Museum's exhibit.  Stop by
>> and
>>> say hi!
>>> 
>>> - Josh
>> 
>> 
>> 
>> --
>> @ BillDeg:
>> Web: vintagecomputer.net
>> Twitter: @billdeg 
>> Youtube: @billdeg 
>> Unauthorized Bio 
> 
> 
> 
> -- 
>   Ian Finder
>   (206) 395-MIPS
>   ian.fin...@gmail.com

Re: MicroVax II update

[Jerry Weiss]

On Aug 5, 2016, at 3:48 PM, dersc...@gmail.com wrote:
> 
>> On Aug 5, 2016, at 1:42 PM, Douglas Taylor  wrote:
>> 
>> Progress on getting the MVII up and running:
>> 
>> I ordered the SCSI2SD adapter and it has come in, the plan is to use it as 
>> the system disk on the MVII.
>> 
>> The hobbyist VMS PAKS have arrived and I was able to download the VMS 7.3 
>> iso, not sure what I can do with it since I think it must be burned to a 512 
>> byte sector CD.
> 
> Burn it to a CD.  Shouldn't be anything complex here.
> 
>> 
>> I asked if the PAKS were good for older versions of VMS, like 5.5, and was 
>> told yes they were.  We'll see about that.

Yes - I have used the same PAK on 5.5 and 7.3.

>> 
>> The Hobbyist VMS CD I had for VMS 7.2 was found and I was able to get the 
>> old Toshiba CD drive to work on the MV 4000 using a CQD 223A.  How can I 
>> create an image of these CD's on the VAX 4000 that I could use in an 
>> emulator?
>> 
>> I wasn't able to get the UC07 to see the CDROM because of a bad SCSI cable, 
>> I had hoped to format the SCSI2SD using the UC07
> 
> Keep in mind that the SCSI2SD can pretend to be a CD-ROM, and can emulate up 
> to 4 SCSI devices at one go.  No need to futz with a real drive if you don't 
> want to...
> 
>> 
>> Is it possible to use the SCSI2SD on a microPDP-11 under RT-11? I ask 
>> because of the disk size limit under RT-11.’

Yes.  It works well with the later versions of RT11 V5.5-5.7. There are DU 
Handlers (MSCP) that allow a large disk  to be partitioned (in the handler) 
into multiple drives  I’ve used up to 7 in RT and 20+ in TSX+ drives at the 
same time.   Each drive is still limited to 32Mb per partition, but you can 
manage up to 255 partitions (~8GB).

Jerry

Re: SWTPC 6800

[Chuck Guzis]

On 08/05/2016 02:15 PM, Brad H wrote:
> I think I will have to figure out how to do that.  Additionally I
> have one of those PC based oscilloscopes on the way.  I don't know
> how to use them 100% but I'm about to learn I guess. :)
> 
> I have one more question for you guys -- I have a few CT-1024
> terminals and would really like this system to work with one of
> those.  However, all of the CTs are quite delicate and are set I
> think for 7, E, 2 @ 110 baud via soldered jumpers.  I'm a bit
> reluctant to try pulling them apart to get in there and fix that.  Is
> there a way to change the parity, etc settings on the SWTPC to match
> the terminal?  Is it necessary?

Well, 110 bps is a bit on the slow side--great for teletypes, not so
much for video terminals.   But you'll have to change the hardwired
jumpers--the UART used in the CT1024 is not software-programmable.

If this were my unit, I"d probably solder some pins into the pad holes
and then either use slide on jumpers or wirewrap to set the
characteristics.  That way, when changing things around, you won't be
stressing the PCB.

Something like this:

http://www.ebay.com/itm/10PCS-20CFemale-to-Female-1-Pin-Plug-Jumper-Cable-Wires-Multicolor-K-/262158878688?hash=item3d09e307e0:g:B-MAAOSwwE5WVLR6

Search on "female jumper wires"

--Chuck

RE: [IBM1130] 029 keypunch available

[John Ball]

Make this yet another person as well in BC who would be jumping on it . I
got almost no use for a card reader if I have no way to punch the cards.

>Ditto.  I'd be all over that if I wasn't in BC.

Re: VCF West - going?

[Brad H]

Is anyone shooting video for those of us that can't go?  I really enjoyed the 
videos of VCF East I found on Youtube.  I'll likely never get to one of these 
things being up here in Canada.. still fun to check out virtually.
Brad


Sent from my Samsung device

 Original message 
From: Curious Marc  
Date: 2016-08-05  3:03 PM  (GMT-08:00) 
To: "General Discussion: On-Topic and Off-Topic Posts"  
Subject: Re: VCF West - going? 

I'll be there with some of my HP equipment. On my way there soon.
Marc

Sent from my iPad

> On Aug 5, 2016, at 10:08 AM, Ian Finder  wrote:
> 
> I'll be there. Flying down from Seattle after work with an Amiga 4000 060
> and a GRiD in my carry-on.
> I wanted to bring a Symbolics machine, but they happen to be quite heavy. ;)
> 
> On Fri, Aug 5, 2016 at 10:01 AM, william degnan 
> wrote:
> 
>> I am here now, will be around all day helping set up.  I have not been to
>> the CHM since the last VCF...The space for the event looks good, tables are
>> out and waiting for exhibitors.
>> 
>>> On Fri, Aug 5, 2016 at 12:07 PM, Josh Dersch  wrote:
>>> 
>>> On Thu, Aug 4, 2016 at 12:25 PM, Ali  wrote:
>>> 
> I am heading to VCF West after a stop over in San Fran today...I am
> looking forward to meeting up with everyone.  I will be there all day
> Friday as a set-up volunteer, Sat and Sunday morning.  I was at the
> last VCF before it was called "West" ... it's been too long.
 
 I am going to be there both days and look forward to meeting people In
 Real Life (TM). So should the list members get special badges or
>>> something
 so people can know who is who? Or *GASP* are we going to have to be
 personable and talk to each other! :D
 
 -Ali
>>> I'll be there co-running the Living Computer Museum's exhibit.  Stop by
>> and
>>> say hi!
>>> 
>>> - Josh
>> 
>> 
>> 
>> --
>> @ BillDeg:
>> Web: vintagecomputer.net
>> Twitter: @billdeg 
>> Youtube: @billdeg 
>> Unauthorized Bio 
> 
> 
> 
> -- 
>   Ian Finder
>   (206) 395-MIPS
>   ian.fin...@gmail.com

Re: AT&T 3b2, IBM RT, others

[Ken Seefried]

I'd really like the AT&T 4425 terminal, which doesn't seem to have
been claimed.  I spent a couple of years with one on my desk.  Any
chance they'd ship?

My wife and I have an agreement that if I bring home any more VME kit
I have to get rid of an equivalent tonnage of other things.  So unless
that Motorola tower is an 88200 or something suitable esoteric, I
probably need to pass.

The E&S box looks like a Sun 3/110 or 4/110 with additional boards.
I'd love to have one.

Obviously, I would have killed for the Explorer or the RTs.  Double
kill for the 5620.  Good they've found homes.

KJ

Re: MicroVax II update

[Douglas Taylor]

On 8/5/2016 4:48 PM, dersc...@gmail.com wrote:



On Aug 5, 2016, at 1:42 PM, Douglas Taylor  wrote:

Progress on getting the MVII up and running:

I ordered the SCSI2SD adapter and it has come in, the plan is to use it as the 
system disk on the MVII.

The hobbyist VMS PAKS have arrived and I was able to download the VMS 7.3 iso, 
not sure what I can do with it since I think it must be burned to a 512 byte 
sector CD.

Burn it to a CD.  Shouldn't be anything complex here.
I was able to expand the compressed file using 7-Zip and generate the 
iso image.  However, when I tried to burn the iso to a CD Win7 reported 
that 'The selected disk image file is not valid'.  Not sure what all 
that means, but anyway VMS can't handle a CD with 2048 block size so I 
stopped fooling around with that.



I asked if the PAKS were good for older versions of VMS, like 5.5, and was told 
yes they were.  We'll see about that.

The Hobbyist VMS CD I had for VMS 7.2 was found and I was able to get the old 
Toshiba CD drive to work on the MV 4000 using a CQD 223A.  How can I create an 
image of these CD's on the VAX 4000 that I could use in an emulator?

I wasn't able to get the UC07 to see the CDROM because of a bad SCSI cable, I 
had hoped to format the SCSI2SD using the UC07

Keep in mind that the SCSI2SD can pretend to be a CD-ROM, and can emulate up to 
4 SCSI devices at one go.  No need to futz with a real drive if you don't want 
to...

Josh
Yes, I believe that is the way to proceed.  Let the SCSI2SD be a couple 
of drives, one for installing the software onto and another to contain 
the installation CD image.  At this point it is kind of a 'chicken and 
the egg' thing for me, the only scsi interface I have is on the VAX.  I 
don't have one on the PC where the VMS image is, so I'm perplexed as to 
how I get the software installation CD onto the SCSI2SD SD card.



Is it possible to use the SCSI2SD on a microPDP-11 under RT-11? I ask because 
of the disk size limit under RT-11.

Doug

Re: MicroVax II update

[Douglas Taylor]

On 8/5/2016 6:18 PM, Jerry Weiss wrote:

On Aug 5, 2016, at 3:48 PM, dersc...@gmail.com wrote:

On Aug 5, 2016, at 1:42 PM, Douglas Taylor  wrote:

Progress on getting the MVII up and running:

I ordered the SCSI2SD adapter and it has come in, the plan is to use it as the 
system disk on the MVII.

The hobbyist VMS PAKS have arrived and I was able to download the VMS 7.3 iso, 
not sure what I can do with it since I think it must be burned to a 512 byte 
sector CD.

Burn it to a CD.  Shouldn't be anything complex here.


I asked if the PAKS were good for older versions of VMS, like 5.5, and was told 
yes they were.  We'll see about that.

Yes - I have used the same PAK on 5.5 and 7.3.


The Hobbyist VMS CD I had for VMS 7.2 was found and I was able to get the old 
Toshiba CD drive to work on the MV 4000 using a CQD 223A.  How can I create an 
image of these CD's on the VAX 4000 that I could use in an emulator?

I wasn't able to get the UC07 to see the CDROM because of a bad SCSI cable, I 
had hoped to format the SCSI2SD using the UC07

Keep in mind that the SCSI2SD can pretend to be a CD-ROM, and can emulate up to 
4 SCSI devices at one go.  No need to futz with a real drive if you don't want 
to...


Is it possible to use the SCSI2SD on a microPDP-11 under RT-11? I ask because 
of the disk size limit under RT-11.’

Yes.  It works well with the later versions of RT11 V5.5-5.7. There are DU 
Handlers (MSCP) that allow a large disk  to be partitioned (in the handler) 
into multiple drives  I’ve used up to 7 in RT and 20+ in TSX+ drives at the 
same time.   Each drive is still limited to 32Mb per partition, but you can 
manage up to 255 partitions (~8GB).

Jerry



Jerry;

I am starting to read about the SCSI2SD and it will be very useful to 
have it emulate multiple drives, I am thinking of one hard disk and up 
to 3 CDROMs, one each for 5.5, 7.2 and 7.3.  If I want to use one of the 
SCSI id's for an image of a VMS installation CD do I make its size 
exactly match the size of the iso image (534MB for 7.3)?


My problem is that the only computer with a SCSI interface in my 
possession is the VAX (and microPDP11), so I will be forced to install 
from an actual CD.  This isn't that bad though, I installed 7.2 about 12 
years ago on the VAX 4000 that I have.


About RT-11, I had 5.4 and it allowed you to use multiple 32MB 
partitions, when I finish with the VAX I will start on the microPDP11.  
I was just curious if you could use the SCSI2SD adapter with RT-11, it 
looks like I can, thanks.


I am at a loss to figure out how to get data onto the SD card partitions 
outside of VMS, will simh recognize the partitions?


Doug

Re: MicroVax II update

[Josh Dersch]

On Fri, Aug 5, 2016 at 7:44 PM, Douglas Taylor 
wrote:

> On 8/5/2016 4:48 PM, dersc...@gmail.com wrote:
>
>>
>> On Aug 5, 2016, at 1:42 PM, Douglas Taylor 
>>> wrote:
>>>
>>> Progress on getting the MVII up and running:
>>>
>>> I ordered the SCSI2SD adapter and it has come in, the plan is to use it
>>> as the system disk on the MVII.
>>>
>>> The hobbyist VMS PAKS have arrived and I was able to download the VMS
>>> 7.3 iso, not sure what I can do with it since I think it must be burned to
>>> a 512 byte sector CD.
>>>
>> Burn it to a CD.  Shouldn't be anything complex here.
>>
> I was able to expand the compressed file using 7-Zip and generate the iso
> image.  However, when I tried to burn the iso to a CD Win7 reported that
> 'The selected disk image file is not valid'.  Not sure what all that means,
> but anyway VMS can't handle a CD with 2048 block size so I stopped fooling
> around with that.


The built-in ISO burning support in Win7 is garbage, use something like
ImgBurn or the like to do the job.


>
>
>> I asked if the PAKS were good for older versions of VMS, like 5.5, and
>>> was told yes they were.  We'll see about that.
>>>
>>> The Hobbyist VMS CD I had for VMS 7.2 was found and I was able to get
>>> the old Toshiba CD drive to work on the MV 4000 using a CQD 223A.  How can
>>> I create an image of these CD's on the VAX 4000 that I could use in an
>>> emulator?
>>>
>>> I wasn't able to get the UC07 to see the CDROM because of a bad SCSI
>>> cable, I had hoped to format the SCSI2SD using the UC07
>>>
>> Keep in mind that the SCSI2SD can pretend to be a CD-ROM, and can emulate
>> up to 4 SCSI devices at one go.  No need to futz with a real drive if you
>> don't want to...
>>
>> Josh
>>
> Yes, I believe that is the way to proceed.  Let the SCSI2SD be a couple of
> drives, one for installing the software onto and another to contain the
> installation CD image.  At this point it is kind of a 'chicken and the egg'
> thing for me, the only scsi interface I have is on the VAX.  I don't have
> one on the PC where the VMS image is, so I'm perplexed as to how I get the
> software installation CD onto the SCSI2SD SD card.


You can do it pretty easily if you have an SD card reader in your PC --
what I'd do is DD the image onto the SD card starting at block zero (there
are numerous dd-like tools for windows for doing this sort of thing).  Then
configure the SCSI2SD to present the first N sectors of the SD card (where
N is the number of 512-byte sectors in the CD image) as a CD-ROM, and use
the rest of the SD card for disks.

- Josh





>
>
>> Is it possible to use the SCSI2SD on a microPDP-11 under RT-11? I ask
>>> because of the disk size limit under RT-11.
>>>
>>> Doug
>>>
>>>
>

Re: the value of old test and repair equipment

[dwight]

I've been restoring a HeathKit capacitor checker.

I also have a couple HP counters with Nixies.

I even have a 10 channel printer ( need to repair the

roller ). I've found that one doesn't need the expensive

ink roller ( though I'd love to have one, used or not ).

I use the two layer impact paper.

Dwight



From: cctalk  on behalf of Ian S. King 

Sent: Sunday, July 31, 2016 3:46:13 PM
To: General Discussion: On-Topic and Off-Topic Posts
Subject: Re: the value of old test and repair equipment

I really like my old test gear and yes, it just seems right to be restoring
vintage computers with vintage instruments.  HP scopes, logic analyzers,
DVMs; function generator; Tek scope, frequency counter; as well as just
'sundry'.  But I did break down and buy a DDS frequency generator to work
on my VHF/UHF ham gear.

On Sat, Jul 30, 2016 at 6:07 PM, drlegendre .  wrote:

> In fact, the value of old test gear varies tremendously..
>
> Vacuum tube testers of certain makes & models are near the top of the food
> chain, with clean, working examples pulling $1500+ (USD) on a very regular
> basis.
>
> There's also a strong following for much 'classic' audio analysis gear (HD
> meters, ID meters, spectrum analyzers, etc.) some very fine multi-meters
> and anything really hi-end like General Radio, Breull & Kejjr, HP, and so
> forth.
>
> Some very early examples from the 1910s to 30's also pull good value simply
> for visual appeal. Much of this gear is resplendent with embossed, enameled
> panels, sculpted Bakelite knobs, large meter movements and an overall Art
> Deco styling.
>
> Seen a nice Supreme Diagnometer recently? Or any of the 40s-70s era English
> made tube testers, like the AVO? Hickok also made a series of bench VTVMs
> with massive chromed meters, designed to be large enough that they can be
> read from many feet away.. those are beautiful for display, and guess what
> - they work great, too!
>
> On Thu, Jul 28, 2016 at 5:24 PM, Dale H. Cook  wrote:
>
> > At 03:52 PM 7/28/2016, Electronics Plus wrote:
> >
> > >... does as-is old test and repair equip that won't be particularly
> cheap
> > have interest to you guys?
> >
> > It depends entirely on the make and model of equipment. I always have a
> > laundry list of stuff I am looking for - one of the reasons why I bring
> my
> > tablet to meets.
> >
> > Dale H. Cook, GR / HP Collector, Roanoke/Lynchburg, VA
> > http://plymouthcolony.net/starcity/radios/index.html
> >
> >
>



--
Ian S. King, MSIS, MSCS, Ph.D. Candidate
The Information School 
Dissertation: "Why the Conversation Mattered: Constructing a Sociotechnical
Narrative Through a Design Lens

Archivist, Voices From the Rwanda Tribunal 
Value Sensitive Design Research Lab 

University of Washington

There is an old Vulcan saying: "Only Nixon could go to China."

Re: How to get a Heathkit H8 to work with a serial terminal

[dwight]

Hi

 Note that the combo card does not work reliably above

4800 baud. It feeds the serial through an optical isolator,

even when doing RS232. It is really intended to do current loop

at lower speeds.

Dwight



From: cctalk  on behalf of Bill Sudbrink 

Sent: Monday, August 1, 2016 6:01:21 PM
To: 'General Discussion: On-Topic and Off-Topic Posts'
Subject: RE: How to get a Heathkit H8 to work with a serial terminal

Try in the SEBHC group:

se...@googlegroups.com

Re: MicroVax II update

[Jerry Weiss]

> On Aug 5, 2016, at 10:24 PM, Douglas Taylor  wrote:
> 
> On 8/5/2016 6:18 PM, Jerry Weiss wrote:
>> On Aug 5, 2016, at 3:48 PM, dersc...@gmail.com wrote:
 On Aug 5, 2016, at 1:42 PM, Douglas Taylor  wrote:
 
 Progress on getting the MVII up and running:
 
 I ordered the SCSI2SD adapter and it has come in, the plan is to use it as 
 the system disk on the MVII.
 
 The hobbyist VMS PAKS have arrived and I was able to download the VMS 7.3 
 iso, not sure what I can do with it since I think it must be burned to a 
 512 byte sector CD.
>>> Burn it to a CD.  Shouldn't be anything complex here.
>>> 
 I asked if the PAKS were good for older versions of VMS, like 5.5, and was 
 told yes they were.  We'll see about that.
>> Yes - I have used the same PAK on 5.5 and 7.3.
>> 
 The Hobbyist VMS CD I had for VMS 7.2 was found and I was able to get the 
 old Toshiba CD drive to work on the MV 4000 using a CQD 223A.  How can I 
 create an image of these CD's on the VAX 4000 that I could use in an 
 emulator?
 
 I wasn't able to get the UC07 to see the CDROM because of a bad SCSI 
 cable, I had hoped to format the SCSI2SD using the UC07
>>> Keep in mind that the SCSI2SD can pretend to be a CD-ROM, and can emulate 
>>> up to 4 SCSI devices at one go.  No need to futz with a real drive if you 
>>> don't want to...
>>> 
 Is it possible to use the SCSI2SD on a microPDP-11 under RT-11? I ask 
 because of the disk size limit under RT-11.’
>> Yes.  It works well with the later versions of RT11 V5.5-5.7. There are 
>> DU Handlers (MSCP) that allow a large disk  to be partitioned (in the 
>> handler) into multiple drives  I’ve used up to 7 in RT and 20+ in TSX+ 
>> drives at the same time.   Each drive is still limited to 32Mb per 
>> partition, but you can manage up to 255 partitions (~8GB).
>> 
> Jerry;
> 
> I am starting to read about the SCSI2SD and it will be very useful to have it 
> emulate multiple drives, I am thinking of one hard disk and up to 3 CDROMs, 
> one each for 5.5, 7.2 and 7.3.  If I want to use one of the SCSI id's for an 
> image of a VMS installation CD do I make its size exactly match the size of 
> the iso image (534MB for 7.3)?
> 

I haven’t used the SCSI2SD to emulate a CDROM, so I gladly defer to others to 
who have done it.  Your basic approach makes sense to me.  Just write the image 
directly to the blocks on a SD that match the starting offset for the partition 
you use in SCSI2SD and leave the blocksize as 512.I used DD on Linux or OSX 
and its easily to pipe images on and off the SD.   For Windows YMMV.

In my case I used a OSX to burn the VMS 7.3 iso to a CDROM.  Then I booted it 
on a Microvax 3100 and built a system.   From there I netbooted the MicroVax 
II.  Since then I also was have moved and booted the same SD images on the  
Microvax 3100, MV II and MV III using a UC07 (no SD partitions).If you can 
attach the SCSI2CD to the your VAX4000 Qbus, you can try the same.  I don’t 
think the KFQSA will work however.

> My problem is that the only computer with a SCSI interface in my possession 
> is the VAX (and microPDP11), so I will be forced to install from an actual 
> CD.  This isn't that bad though, I installed 7.2 about 12 years ago on the 
> VAX 4000 that I have.
> 
> About RT-11, I had 5.4 and it allowed you to use multiple 32MB partitions, 
> when I finish with the VAX I will start on the microPDP11.  I was just 
> curious if you could use the SCSI2SD adapter with RT-11, it looks like I can, 
> thanks.
> 

SCSI2SD works fine with RT11 and my UC07.

> I am at a loss to figure out how to get data onto the SD card partitions 
> outside of VMS, will simh recognize the partitions?

You can probably install cygwin on your Windows machine  It has dd and other 
byte banging tools to facilitate the transfer.  Alternately boot a Linux CDROM. 
  The SD card itself knows not of the partitions.  This geometry is stored in 
the SCSI2SD.

Jerry

Re: the value of old test and repair equipment

[drlegendre .]

"I've been restoring a HeathKit capacitor checker."

Which one, the IT-28? Those are really handy for finding leakage in
high-voltage caps, as they have a crazy-high (like 600V ?) power supply.
Unlike modern SS units, the IT-28 can test at practical working voltages.

There's data out there on how to finely calibrate those units, but I don't
see much point in it.. It's a lot of fiddly work and for what - to have the
best 40-year-old LCR meter? If you want a better than ballpark measure of L
or C, get one of the cheap uC-based swiss knife testers. A set of 1% metal
film resistors are cheap, though, and will improve stability.

If you ever feel the need to do semi-precision work with a device like the
IT-28, you're best off running it as a comparator and keeping a set of
precision value caps for reference. In that case, you only need to make
sure you have well matched resistor pairs in the bridge circuit.

On Fri, Aug 5, 2016 at 10:47 PM, dwight  wrote:

> I've been restoring a HeathKit capacitor checker.
>
> I also have a couple HP counters with Nixies.
>
> I even have a 10 channel printer ( need to repair the
>
> roller ). I've found that one doesn't need the expensive
>
> ink roller ( though I'd love to have one, used or not ).
>
> I use the two layer impact paper.
>
> Dwight
>
>
> 
> From: cctalk  on behalf of Ian S. King <
> isk...@uw.edu>
> Sent: Sunday, July 31, 2016 3:46:13 PM
> To: General Discussion: On-Topic and Off-Topic Posts
> Subject: Re: the value of old test and repair equipment
>
> I really like my old test gear and yes, it just seems right to be restoring
> vintage computers with vintage instruments.  HP scopes, logic analyzers,
> DVMs; function generator; Tek scope, frequency counter; as well as just
> 'sundry'.  But I did break down and buy a DDS frequency generator to work
> on my VHF/UHF ham gear.
>
> On Sat, Jul 30, 2016 at 6:07 PM, drlegendre . 
> wrote:
>
> > In fact, the value of old test gear varies tremendously..
> >
> > Vacuum tube testers of certain makes & models are near the top of the
> food
> > chain, with clean, working examples pulling $1500+ (USD) on a very
> regular
> > basis.
> >
> > There's also a strong following for much 'classic' audio analysis gear
> (HD
> > meters, ID meters, spectrum analyzers, etc.) some very fine multi-meters
> > and anything really hi-end like General Radio, Breull & Kejjr, HP, and so
> > forth.
> >
> > Some very early examples from the 1910s to 30's also pull good value
> simply
> > for visual appeal. Much of this gear is resplendent with embossed,
> enameled
> > panels, sculpted Bakelite knobs, large meter movements and an overall Art
> > Deco styling.
> >
> > Seen a nice Supreme Diagnometer recently? Or any of the 40s-70s era
> English
> > made tube testers, like the AVO? Hickok also made a series of bench VTVMs
> > with massive chromed meters, designed to be large enough that they can be
> > read from many feet away.. those are beautiful for display, and guess
> what
> > - they work great, too!
> >
> > On Thu, Jul 28, 2016 at 5:24 PM, Dale H. Cook 
> wrote:
> >
> > > At 03:52 PM 7/28/2016, Electronics Plus wrote:
> > >
> > > >... does as-is old test and repair equip that won't be particularly
> > cheap
> > > have interest to you guys?
> > >
> > > It depends entirely on the make and model of equipment. I always have a
> > > laundry list of stuff I am looking for - one of the reasons why I bring
> > my
> > > tablet to meets.
> > >
> > > Dale H. Cook, GR / HP Collector, Roanoke/Lynchburg, VA
> > > http://plymouthcolony.net/starcity/radios/index.html
> > >
> > >
> >
>
>
>
> --
> Ian S. King, MSIS, MSCS, Ph.D. Candidate
> The Information School 
> Dissertation: "Why the Conversation Mattered: Constructing a Sociotechnical
> Narrative Through a Design Lens
>
> Archivist, Voices From the Rwanda Tribunal 
> Value Sensitive Design Research Lab 
>
> University of Washington
>
> There is an old Vulcan saying: "Only Nixon could go to China."
>

IBM Diskette OEM Information manuals wanted

[Eric Smith]

Does anyone happen to have the IBM Diskette OEM Information manuals:
GA21-9190  one-sided
GA21-9257  two-sided

I'm specifically NOT looking for the Diskette General Information
Manual, GA21-9182, unless someone has an edition earlier than Fourth
or later than Sixth.

The OEM Information manuals were the definitive reference for the
track formats for eight-inch diskettes. Generally equivalent
information is available from a lot of later sources, including ECMA,
ISO, and ANSI standards, and from vendor datasheets and application
notes for floppy drives and floppy disk controller chips, though I've
encountered a number of inaccuracies in vendor documentation.

The ECMA standards are available online. I'm interested in the IBM OEM
information manuals primarily for historical reasons, not because I'm
missing any particular technical information.

Thanks!
Eric

Re: SWTPC 6800

[Brad H]

Okay so.. I decided to try the MP-C board out, just for kicks.  No change.
Then I decided to add one of the RAM boards.. the next one up in addresses.  
Got a little bit when I powered on.  Added one of the old MPM boards.. one that 
has memory chips all piggybacked on one another.  Now when I powered up, the 
system was sending four or five characters at a time, linefeed, four or five 
characters at a time, linefeed ad infinitum.  I added the final MPM board.. 
zero.
So.. I think we do have some ram problems.. most likely.  I'm thinking it would 
be easiest to concentrate efforts on the socketed RAM boards.. test all the RAM 
out.  I'm going to read up on addressing and try to understand a bit better 
what is going on.  I'm thinking maybe I need to reconfigure the addressing on 
one of the boards to match whatever that overstuffed MPM board is set to.
Until I get an oscilloscope.. fooling around is about all I can do here.


Sent from my Samsung device

 Original message 
From: Chuck Guzis  
Date: 2016-08-05  3:55 PM  (GMT-08:00) 
To: "General Discussion: On-Topic and Off-Topic Posts"  
Subject: Re: SWTPC 6800 

On 08/05/2016 02:15 PM, Brad H wrote:
> I think I will have to figure out how to do that.  Additionally I
> have one of those PC based oscilloscopes on the way.  I don't know
> how to use them 100% but I'm about to learn I guess. :)
> 
> I have one more question for you guys -- I have a few CT-1024
> terminals and would really like this system to work with one of
> those.  However, all of the CTs are quite delicate and are set I
> think for 7, E, 2 @ 110 baud via soldered jumpers.  I'm a bit
> reluctant to try pulling them apart to get in there and fix that.  Is
> there a way to change the parity, etc settings on the SWTPC to match
> the terminal?  Is it necessary?

Well, 110 bps is a bit on the slow side--great for teletypes, not so
much for video terminals.   But you'll have to change the hardwired
jumpers--the UART used in the CT1024 is not software-programmable.

If this were my unit, I"d probably solder some pins into the pad holes
and then either use slide on jumpers or wirewrap to set the
characteristics.  That way, when changing things around, you won't be
stressing the PCB.

Something like this:

http://www.ebay.com/itm/10PCS-20CFemale-to-Female-1-Pin-Plug-Jumper-Cable-Wires-Multicolor-K-/262158878688?hash=item3d09e307e0:g:B-MAAOSwwE5WVLR6

Search on "female jumper wires"

--Chuck

Re: SWTPC 6800

[Brent Hilpert]

Do you have some RAM at $A000+ yet?
That's all that should matter as far as required RAM goes.

Presuming this is the holley page you were referring to:
http://www.swtpc.com/mholley/HiTerm/Test6800_Index.html
he does mention RAM needed at A000 for the BUGs, as Chris and I have been 
saying.

Without RAM there there's no stack for return addresses for subroutines 
executed in the BUGs, so execution could head off to wherever.


On 2016-Aug-05, at 10:23 PM, Brad H wrote:
> Okay so.. I decided to try the MP-C board out, just for kicks.  No change.
> Then I decided to add one of the RAM boards.. the next one up in addresses.  
> Got a little bit when I powered on.  Added one of the old MPM boards.. one 
> that has memory chips all piggybacked on one another.  Now when I powered up, 
> the system was sending four or five characters at a time, linefeed, four or 
> five characters at a time, linefeed ad infinitum.  I added the final MPM 
> board.. zero.
> So.. I think we do have some ram problems.. most likely.  I'm thinking it 
> would be easiest to concentrate efforts on the socketed RAM boards.. test all 
> the RAM out.  I'm going to read up on addressing and try to understand a bit 
> better what is going on.  I'm thinking maybe I need to reconfigure the 
> addressing on one of the boards to match whatever that overstuffed MPM board 
> is set to.
> Until I get an oscilloscope.. fooling around is about all I can do here.
> 
> Sent from my Samsung device
> 
>  Original message 
> From: Chuck Guzis  
> Date: 2016-08-05  3:55 PM  (GMT-08:00) 
> To: "General Discussion: On-Topic and Off-Topic Posts" 
>  
> Subject: Re: SWTPC 6800 
> 
> On 08/05/2016 02:15 PM, Brad H wrote:
>> I think I will have to figure out how to do that.  Additionally I
>> have one of those PC based oscilloscopes on the way.  I don't know
>> how to use them 100% but I'm about to learn I guess. :)
>> 
>> I have one more question for you guys -- I have a few CT-1024
>> terminals and would really like this system to work with one of
>> those.  However, all of the CTs are quite delicate and are set I
>> think for 7, E, 2 @ 110 baud via soldered jumpers.  I'm a bit
>> reluctant to try pulling them apart to get in there and fix that.  Is
>> there a way to change the parity, etc settings on the SWTPC to match
>> the terminal?  Is it necessary?
> 
> Well, 110 bps is a bit on the slow side--great for teletypes, not so
> much for video terminals.   But you'll have to change the hardwired
> jumpers--the UART used in the CT1024 is not software-programmable.
> 
> If this were my unit, I"d probably solder some pins into the pad holes
> and then either use slide on jumpers or wirewrap to set the
> characteristics.  That way, when changing things around, you won't be
> stressing the PCB.
> 
> Something like this:
> 
> http://www.ebay.com/itm/10PCS-20CFemale-to-Female-1-Pin-Plug-Jumper-Cable-Wires-Multicolor-K-/262158878688?hash=item3d09e307e0:g:B-MAAOSwwE5WVLR6
> 
> Search on "female jumper wires"