lattice jtag
Hi, thanks for the schematic, I've searched through a few of their manuals but I obviously overlooked it
.
I am having real trouble getting this chip programmed, I've got the latest software from lattice, ispVM. And I've prototyped several designs, which are basically all very similar, they all have the same connections to the parallel port and simply buffer them with a 74hc244.
Maybe its a power issue? I'm powering the programming board with a 5v regulator, powered form a 9v battery, the whole circuit goes as follows:
COmputer -> Parallel cable (m-m, about 1.7m) -> Parallel female socket, soldered on pins 2,3,4,5,6,8,10,12,15,18-25. -> 74Hc244, via resisitors, -> PLCC44 Socket containing the M4A5-64/32.
I've just checked the parallel cable, and all pins are connected individually from end to end.
As for the software, the jedec file cannot be a problem, since I haven't got to the stage where its needed. The VM software detects when its plugged in (port pins 8 and 12 linked), it detects when the power is on (pin 15 I believe), but it refuses to go any further, constantly spitting out the same old line 'Programmer: Not available'.
If there is an 'easier' way, I'm all ears, I've prototyped so many different configurations, soldered the DB25 connector so many times that its melted, and the software resfuses to play ball of give any assistance.
Regards,
BuriedCode.