There are numerous ways to do this Frank, I opted for the most basic hardware approach using 74LSxxx. This allows for very simple hardware debugging. Later one can easily use and learn how the S100 bus signals are generated/formed etc. using a scope/logic probe step by step. The challenge with boards like this is getting them working with older pre IEEE-696 S100 boards found in many S100 boxes. Few even old Z80 boards worked with all boards.
Having spent the best part of a year on a CPLD based 80386 and 80486 based S100 boards I can tell you it's not as easy as you may think. That said if you have time I'm sure some S100 users would appreciate a CPLD Z80 board. John PS can you also add your name to the S100Computers GG:- https://groups.google.com/forum/?fromgroups#!forum/s100computers John -----Original Message----- From: [email protected] [mailto:[email protected]] Sent: Wednesday, October 14, 2015 11:57 AM To: [email protected] Subject: RE: [N8VEM-S100:7747] Re: A new Z80 based SBC to get beginners started on the S100 bus Hello All, This is my first time with the group, so please bear with me. I agree with "ICyoung" that the CPU board should be simple, and like the idea of a USB link to a host computer to provide low cost terminal/loader/storage. Assume a person has an S100 bus system, the idea is to start with the CPU board. Then a board at a time can be added, working with the CPU board to check out each board and get it working before going to the next. Using a CPLD for the logic would probably be easiest as they can be programmed from an old style PC printer port with an easily built cable. There is software to make a schematic using standard TTL parts, and then compile and load it. Providing a simplified CPU board that can be used for system checkout and wouldn't cost a great deal would help the beginner a lot. If simple enough it could be professionally built, providing a "plug and play" environment for us dummies. - Frank Wilson -- You received this message because you are subscribed to the Google Groups "N8VEM-S100" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "N8VEM-S100" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
