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Altera_Forum
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16 years ago

Help me!

Hi every one ! I actually wanna get your hand cause I was doing with EPM7064SLC44-10( MAX7000S) but I have problem with JTAG, I can't load it and now it makes me trouble!.. Please fix me the problem ...
Altera_Forum's avatar
Altera_Forum
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16 years ago

Altera's guidelines recommend TCK be tied to GND through a 1K resistor.

I don't have Altium Designer and haven't looked at your schematic. However, I've found that many JTAG signal integrity problems can be solved by adding source-series termination to the JTAG signals. So for example, a 33ohm or 50ohm resistor on TCK, TDI, and TMS right at your JTAG connector. Also, a resistor on TDO coming out of the FPGA.

I'm not saying this is your issue. Usually if signal integrity is a problem, you'll at least be able to scan the chain even if only intermittently.

Jake