Thanks and Good points Gary,
Could I add… The default mode for the Z80 (& 8086 & 80386) monitors is NO IOBYTE port present. I.E. the monitor will always read port EF as 0FFH. This will cause the monitor to expect the console I/O to come from the Propeller Console I/O ports (0 & 1) or whatever other arrangement you have programmed in the appropriate modules in your system. The “IOBYTE” concept arose from Roger Amadon’s Zapple’s monitor at TDL back in the late 70’s. It was carried on to CPM for redirection I/O. I have used some bit’s to do other things with CPM as well, but its main use is in debugging hardware with the 8086 and later CPU’s. You really have to be very careful with jumpers for earl y PROMS. See here for a summary:- http://s100computers.com/My%20System%20Pages/PROM%20Board/PROM%20Board.htm As the years go by we are getting better (I think) at laying out and labeling new boards. These days IC’s have their numbers outside the footprint. Jumpers have their function(s) in small fonts beside them and polarized caps/LED’s have their + terminal as a square pad. That said, because of the way freerouter works in finding the shortest possible routes, the pin 1 of jumpers, LED, caps and resistor arrays is NOT the same across the board. Pin 1 is always the square pad but its orientation varies. Be very careful with this. A miss-orientated resistor array is very difficult to detect/debug/remove. Finally I would like to point out that while I try to write-up build instructions is a step by step manner, errors do creep in. Don’t regard the write-up as “Gospel” is you notice a serious error please let me know. John From: [email protected] [mailto:[email protected]] On Behalf Of Gary Kaufman Sent: Thursday, June 11, 2015 6:53 AM To: [email protected] Subject: [N8VEM-S100:7220] Re: Z80 CPU board setup issue I don't have the sophistication/knowledge of may folks here, but at least for me, getting an initial system working was a challenge. I was able to make use of an ADC Super Six board to test out the ram and serial port boards. Some thoughts... Jumpering and wiring connectors on the Console I/O board can be tricky. Remember that the V5.02 monitor is going to read an IOBYTE at 0EFH, which isn't present in your current system. It also needs to be assembled twice for high and low page versions and then combined to burn the Eprom. I also believe jumpering for 2764 and 28C64's are different, but would have to check... Take a reasonable resolution pic of each board and post them, We can compare jumpering etc or may spot errors. I'd be happy to burn you a working 28C64 with V5.02 At least for me, almost every problem ended up being incorrect jumpering, pins that weren't in the socket properly, need to resolder ground connections, or flakey/bad/counterfeit IC's. - Gary On Wednesday, June 10, 2015 at 10:41:45 PM UTC-4, [email protected] wrote: Hi everyone. I just finished building the Z80 board and I am having some problems, so I am hoping that some of you have some ideas. My system is the following: V2-S100 Z80 Master CPU board 4Meg static RAM board Prop I/O board I have the Z80 board jumpered as master. I also have a simple switch for reset. The RAM board is set for 1Meg only at 0000H. -- 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.
