Charles M. Posted April 16, 2020 Share Posted April 16, 2020 Hi everyone, I recently bought an unlabeled program pak on ebay. I bought it for the cartridge case but I wanted to see what program it was. Before plugging it in, I opened the cartridge and surprise, there is no ROM inside! It looks like some kind of prototype board with a few sn74ls244n and one sn74ls245n octal buffers. I'm new to the world of electronics (and CoCo) so I was wondering if someone on this forum ever used something similar. I want to know if it can be of any use. Thank you for you help, Charles Quote Link to comment Share on other sites More sharing options...
brain Posted April 16, 2020 Share Posted April 16, 2020 Someone made a "buffer" board. the 3 '244s buffer the 16 address lines and the control lines (probably R/W, E, Q, CTS, SCS, RESET, but not CART or NMI) and the 245 buffers the 8 data lines. You can then probe all the lines at the cart without risking damage to the CoCo itself. Nice option for experimentors. 1 Quote Link to comment Share on other sites More sharing options...
JamesD Posted April 16, 2020 Share Posted April 16, 2020 There was a ribbon cable attached to that, so it probably interfaced something, but what is anyone's guess. 1 Quote Link to comment Share on other sites More sharing options...
MrDave Posted April 17, 2020 Share Posted April 17, 2020 Most def someone who likes to solder and experiment.. making all the address and data lines available. Could of run anything ! But probably diffrent things from time to time. Neat If you have a logic probe see what beepscand when ! 1 Quote Link to comment Share on other sites More sharing options...
Charles M. Posted April 17, 2020 Author Share Posted April 17, 2020 That sounds like a pretty neat board. I don't have a logic probe yet but I'll try to interface with a microcontroller. I'm sure I can find something to do with it. Thank you all for the replies! ? Quote Link to comment Share on other sites More sharing options...
BillO Posted May 9, 2020 Share Posted May 9, 2020 That should be a cinch to reverse engineer and draw up the schematic. Looks like a universal interface/bus buffer. Not sure why there are 2 '245s as there are only 8 data lines. However, having said that I have stopped using '244s in my projects as they are no cheaper than a '245 and a bitch to layout on a PCB. Draw up the schematic and you'll get a better understanding of what it can offer. 1 Quote Link to comment Share on other sites More sharing options...
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