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 <ccl...@sydex.com> > Date: 2016-08-05 3:55 PM (GMT-08:00) > To: "General Discussion: On-Topic and Off-Topic Posts" > <cctalk@classiccmp.org> > 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"