[cctalk] Re: How much memory?

[Paul Koning via cctalk]

> On Jun 16, 2023, at 8:04 PM, ben via cctalk  wrote:
> 
> On 2023-06-16 4:56 p.m., Chuck Guzis via cctalk wrote:
>> On 6/16/23 12:48, ben via cctalk wrote:
>>> What cpu?
>>> Minix was 16 bit code only. I suspect 16 bit code here as well.
>>> Remember 32 bit code is 2x the size of 16 bit stuff.
>> 32-bit, I'm afraid.   To quote:
>> WHAT IS LINUX?
>>   Linux is a Unix clone for 386/486-based PCs written from scratch by
>>   Linus Torvalds with assistance from a loosely-knit team of hackers
>>   across the Net.  It aims towards POSIX compliance.
>>   It has all the features you would expect in a modern fully-fledged
>>   Unix, including true multitasking, virtual memory, shared libraries,
>>   demand loading, shared copy-on-write executables, proper memory
>>   management and TCP/IP networking.
>>   It is distributed under the GNU General Public License - see the
>>   accompanying COPYING file for more details.
>> --Chuck
> 
> Was that quote written for version #1.
> At risk of being a troll, when did Unix (PDP 11) not have all the the above. 
> Other than TCP/IP networking, I don't see any of above features
> desirable, as I feel a need for more real time operating systems.

BSD 2.11 had TCP/IP.  Anyway, the thing that made Linux special is not its Unix 
nature but that it is an unencumbered Unix-compatible OS.  That was a big deal 
back in the days of restrictive licensing run by the likes of AT&T and many 
others.

> How many OS's are complete in design that you don't need to bypass
> the OS like MS DOS.
> Ben.

For what definition of "need"?  

I have at times needed to go around the OS with MSDOS, with OS/360 and with 
RT-11, but rarely if ever with others ranging from THE to RSTS to CDC NOS.  Of 
course it helps to be able to write device drivers, that takes care of a number 
of the cases.  And at times I have done modifications to the OS, thought not 
usually large ones.  The main exception I can think of is NetBSD, where I 
worked on a storage product that had all the high-speeed functionality inside, 
or more precisely to the side of, NetBSD.  That and the network stack in a 
separate CPU core running an entirely different very skinny RTOS known as 
"QRQ".  (That's a ham radio code for "please transmit faster".)

paul

[cctalk] Re: How much memory?

[Henry Bent via cctalk]

On Sat, 17 Jun 2023 at 10:31, Paul Koning via cctalk 
wrote:

>
> BSD 2.11 had TCP/IP.
>

Later versions of 2.9BSD had TCP/IP though the hardware support was pretty
limited.  And you could probably use the present tense for 2.11BSD, it's
still getting patches.

-Henry

[cctalk] Re: How much memory?

[John Herron via cctalk]

On Fri, Jun 16, 2023, 2:52 PM Paul Koning via cctalk 
wrote:

>
>
> > On Jun 16, 2023, at 3:40 PM, Chuck Guzis via cctalk <
> cctalk@classiccmp.org> wrote:
> >
> > On 6/16/23 12:02, ben via cctalk wrote:
> >
> >> Ken , Jobs and  Wozniak need their fair share.
> >> Graphics and file system buffers take up more
> >> space than you expect.
> >
> > I just transferred a DC150 tar tape.  Total (uncompressed) file size was
> > 11MB.  What was on it?  The complete source to Linux 1.0.
>
> Somewhat earlier, the complete source for the RSTS-11 timesharing system
> fit on 5 DECtapes, 1.5 MB.  And that was assembly language, exhaustively
> commented.


Precisely. Let's not forget the real enemy here.  Commenting our code. ;-)

>
>
>

[cctalk] Re: How much memory?

[Warner Losh via cctalk]

On Fri, Jun 16, 2023 at 6:04 PM ben via cctalk 
wrote:

> On 2023-06-16 4:56 p.m., Chuck Guzis via cctalk wrote:
> > On 6/16/23 12:48, ben via cctalk wrote:
> >
> >> What cpu?
> >> Minix was 16 bit code only. I suspect 16 bit code here as well.
> >> Remember 32 bit code is 2x the size of 16 bit stuff.
> >
> > 32-bit, I'm afraid.   To quote:
> >
> > WHAT IS LINUX?
> >
> >Linux is a Unix clone for 386/486-based PCs written from scratch by
> >Linus Torvalds with assistance from a loosely-knit team of hackers
> >across the Net.  It aims towards POSIX compliance.
> >
> >It has all the features you would expect in a modern fully-fledged
> >Unix, including true multitasking, virtual memory, shared libraries,
> >demand loading, shared copy-on-write executables, proper memory
> >management and TCP/IP networking.
> >
> >It is distributed under the GNU General Public License - see the
> >accompanying COPYING file for more details.
> >
> > --Chuck
> >
>
> Was that quote written for version #1.
> At risk of being a troll, when did Unix (PDP 11) not have all the the
> above. Other than TCP/IP networking, I don't see any of above features
> desirable, as I feel a need for more real time operating systems.
>


The PDP-11 never had useful virtual memory, the 8k segment size was simply
too large to do anything other that interprocess protection and have a
separate address space per process. It never had a useful mmap, so it never
had useful shared libraries, it couldn't demand load binaries (they were
loaded entirely at startup), there was no copy-on-write sharing. Not sure
what 'proper memory management' meant, so can't comment on that

AT&T PDP-11 unix never had TCP/IP from AT&T, though an early NCP version
existed and BBN's TCP stack made V7 and newer have TCP. The BSD side had
TCP/IP, running in a "separate" process from the kernel (it ran in
supervisor mode, to get more address space out of the PDP-11 architecture
while sharing the data segments). 2.9 had TCP/IP, but it wasn't until 2.10
or 2.11 that it was really stable.

How many OS's are complete in design that you don't need to bypass
> the OS like MS DOS.
>

I've evaluated several router products, years ago, that just used Lnux or
FreeBSD to load an application that took over the machine...

Warner

[cctalk] Re: How much memory?

[Bill Gunshannon via cctalk]

On 6/17/2023 10:42 AM, Henry Bent via cctalk wrote:

On Sat, 17 Jun 2023 at 10:31, Paul Koning via cctalk 
wrote:


BSD 2.11 had TCP/IP.


Later versions of 2.9BSD had TCP/IP though the hardware support was pretty
limited.  And you could probably use the present tense for 2.11BSD, it's
still getting patches.



Ultrix-11, which was DEC version of Version 7 had TCP/IP.  I use it all 
the time.



bill

[cctalk] Re: How much memory?

[Warner Losh via cctalk]

On Sat, Jun 17, 2023, 10:38 AM Bill Gunshannon via cctalk <
cctalk@classiccmp.org> wrote:

>
> On 6/17/2023 10:42 AM, Henry Bent via cctalk wrote:
> > On Sat, 17 Jun 2023 at 10:31, Paul Koning via cctalk <
> cctalk@classiccmp.org>
> > wrote:
> >
> >> BSD 2.11 had TCP/IP.
> >>
> > Later versions of 2.9BSD had TCP/IP though the hardware support was
> pretty
> > limited.  And you could probably use the present tense for 2.11BSD, it's
> > still getting patches.
> >
>
> Ultrix-11, which was DEC version of Version 7 had TCP/IP.  I use it all
> the time.
>

I believe the Ultrix 11 had the bsd 2.10 tcp code in it... it had a lot of
Berkeley code in it...

Warner

bill
>
>
>

[cctalk] IBM 5120/5110-3 casual notes / 8" disks question

[Steve Lewis via cctalk]

I finally got an IBM 5120 earlier this month, to complement the 5100 and
5110 that I already have.

It had a few issues, but I did manage to get it to "boot" to BASIC.

I put together a few notes about it here.  Nothing too exciting, but two
things I've learned: (1) the 5120 does actually still have the video
REVERSE feature.  (2) the 5120 has both an external (red power switch) and
internal power switch (internal one is at rear below disk drives).

Notes here:

https://voidstar.blog/ibm-5120-aka-ibm-5110-3/
IBM 5120 (aka IBM 5110-3) — voidstar



My only question is: how "universal" are 8" disk?  This 5120 only came with
a single IBM 8" Diagnostics disk.  It looks to be in fine condition, but
I've no idea about the data.

So far I haven't been able to read it - it's probably more hardware/drive
issues, I'm still investigating.   But I'm wondering if I had other 8"
disks (3M SS/SD), should I be able to format/MARK them?

I've used old tape decks and 5.25" drives - but 8" drives is all new
territory for me.



Also, I'll be talking about the 5100/5110 at VCF next Sunday on the 25th of
this month, June.

[cctalk] Re: IBM 5120/5110-3 casual notes / 8" disks question

[Fred Cisin via cctalk]

On Sat, 17 Jun 2023, Steve Lewis via cctalk wrote:


I finally got an IBM 5120 earlier this month, to complement the 5100 and
5110 that I already have.
. . . 
My only question is: how "universal" are 8" disk?  This 5120 only came with

a single IBM 8" Diagnostics disk.  It looks to be in fine condition, but
I've no idea about the data.
So far I haven't been able to read it - it's probably more hardware/drive
issues, I'm still investigating.   But I'm wondering if I had other 8"
disks (3M SS/SD), should I be able to format/MARK them?
I've used old tape decks and 5.25" drives - but 8" drives is all new
territory for me.


I do not know anything about 5120.

But, several sources mention the drives as being 1.2M
That would be double sided, double density.
Are you sure that you want SS/SD?

One article mentioned 256 bytes per sector, which would be consistent with 
double density, as single density 8" was usually 128 bytes per sector.


You can usually get away with formatting a SD (FM) disk as DD (MFM), but 
SS and DS 8 inch are different!


A few quick things about 8", (which you are likely to already know)
1) write protect is opposite of the way 5.25" does it; an open notch is 
write protected, you need to cover the write protect notch if you want to 
write.


2) single sided and double sided 8" disks have the index hole in the 
jacket in different places.  Therefore, they are not fully 
interchangeable.
single sided disks will often have a "1" on them; double sided sometimes 
have a "2"

"1D" and "2D" are single and double sided, double density.

Some drives have two sets of index sensors, to be able to handle both 
single and double sided; some do not.
Punching additional holes in the jacket does work to convert one to the 
other, which ends up looking a lot like the index holes for the 
hard-sectored disks.


http://www.bitsavers.org/pdf/3M/3M_Diskette_Reference_Manual_May83.pdf
figure 3 shows the locations of the index holes
With a SS and a DS side by side, it's obvious; if you don't have both, . . .
If you imagine a line along the read/write slot, and a line from the 
center of the hub hole, the SS is at a 7 degree angle, and the DS is at a 
26 degree angle


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

[cctalk] Re: IBM 5120/5110-3 casual notes / 8" disks question

[Fred Cisin via cctalk]

1) write protect is opposite of the way 5.25" does it; an open notch is write 
protected, you need to cover the write protect notch if you want to write.


If I remember correctly, in the 1994 "Computer Bowl", Bil Gates' team was 
unable to answer the question about where the write protect notch is on an 
8" disk.It is on the front edge of the disk.  That helps 8" disks to 
leave loose write enable tabs that fall off where they can do more damage.

[cctalk] Re: CPT Phoenix Jr system unit? Monitor and Keyboard

[Chris Hanson via cctalk]

On Jun 7, 2023, at 5:09 PM, Chris Hanson via cctalk  
wrote:
> 
> Sorry I missed this, you only sent it to the list and I haven't looked at the 
> list for a while. I've actually just acquired a CPT Phoenix Jr. computer to 
> go with my display and keyboard, so I now have a full system that I'm 
> planning to restore and use.

I've set up a group at https://groups.io/g/cptphoenixjr for discussion and 
preservation of the CPT Phoenix JR.

I've just posted a little bit about how I'm going about trying to get the ROM 
booting in emulation as a way to figure out how the hardware is attached. Of 
course, if you or anyone else has knowledge here, that'd make everything a lot 
easier than working backwards from the ROM code and peripheral data sheets. :)

  -- Chris