Electronics > Beginners

JTAG diy board for Lattice PLSI1024

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screemo:
Hello,

This is my first post, so excuse me if I sound like a complete newbie.

I have a pair of old CPLD's that I need to program, one of them being a PLSI1024 from Lattice Semiconductor.

My progress so far:

1) Purchased one of the knockoff ispDownload cables (the HW-USBN-2A, which supports 5v devices).
2) Built a small board with the 10-pin JTAG connector, PLCC-68 socket wired up on SDI/SDO/GND/VCC/TMC (also verified all connections are correct).
3) Added a breakout connector on VCC/GND, so that both CPLD and (ideally) ispDownload cable could be powered at the same time.  :-//

Now for the questions:

1) ispDownload cable requires power from the programming board - I tried 5v/10mA (on ispVM it sees the cable on usb, but tells me that no power is found on the board side) - what voltage/amps does it require? (do I need two separate voltages to make this work?)
2) There's mention of a decoupling cap in the documentation for older CPLDs, but as I understand this wouldn't prevent at least the ispDownload cable to be working.
3) I might have missed the ispEN is required for the CPLD to enter programming mode ?

Any pointers appreciated, as I thought it would better to ask someone here that are actually experts on electronics   ;D

screemo:
Turns out I simply didn't read hard enough.

Found a great example of a DIY (ghetto ?  :D) ressource (https://www.instructables.com/id/Ghetto-Programmable-Logic-CPLD-Development-Syste/). This shows that I do not have enough VCC / GND connected and also ispEN is required as I can read further down the docs.

Also the ispDownload cable is apparently powered using 9VDC/200mA.

Once I get it working, I will write my findings here - maybe it helps someone.

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