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Altera_Forum's avatar
Altera_Forum
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17 years ago

can't scan jtag chain in customer built board

I have a custom built board with EPM570T100C3N, this is the only programmable device in the board. The other chip is a CY68013A. The USB part of the board works well, but the CPLD cannot programmed b...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
17 years ago

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But the JTAG hardware is apparently wrong anyway.

Check with an oscilloscope, that each input signal (TCK, TMS, TDI) is arriving at the respective pin. If so, the TDO output must also show a response in initial chain test.

--- Quote End ---

I don't have a oscilloscope, the only thing I have is a multimeter.

I have verified the byteblaster and usbblaster cable in another board that have MAX7000 CPLD on it. Both of the cable are fine. Here is the power and jtag part of the schematic. Is there something wrong ?