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Altera_Forum
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16 years ago

Reprogramming protection?

I want to reprogram a MAX II CPLD (EPM1270T144C5N) with USB-Blaster download cable. Programmer can’t access JTAG chain despite I have verified that voltages on board and on 10-pin male header are rig...
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Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

"Can't access JTAG chain" means that the device isn't accessed at all. It#s usually due to a wiring error. MAX II has a readout protection (security bit) and no overwrite protection. If it had, it would no affect the ability to identify the device on a JTAG chain.

Some older CPLD devives had on option to disable the JTAG interface after programming, but MAX II hasn't. Generally, you should follow the JTAG troubleshooting tips in the MAX II devive manual.