All,
My setup:
MAX-II EPM1270
Quartus 9.0
USB-Blaster
I have designed my own Eval boards for the MAX-II EPM1270. I have no issues programming any of them by themselves.
Now I have tried to connect each board together for the JTAG chain, and I get various errors.
I have tried the textbook connection of 1K, 10K, 100K pullups on any, all, and some combinations to VCC on any and all 4 lines of TMS, TCK, TDI, TDO. I have also configured my setup as described in AN-428 MAX-II CPLD Design Guidelines page 7 which shows a 10K pullup to TMS and a 1K pulldown on TCK and TDI and TDO open... I have also tried different combinations of resistor combinations in this configuration, but I still have no luck.
Sometimes I get an error: Unknowm integrity checking failure....... Then other times I can get it into a mode that shows 11, or 42, or 98, or..... devices in a chain, some with unknown and an IDs and others unknown.
If I remove my jumpers from board to board and use each individual board by itself, everything is good and I can program each board individually all-day-long.
My current design is going to consist of 4-MAX-II EPM1270s on one board and I was wanting to program them with only 1 header vs 4 headers. If I can't breadboard the "simple" JTAG chain, I will result back to 4 individual programming headers.
Anybody have any ideas or suggestions??
Thanks,
Keith
