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Altera_Forum
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14 years ago

Intermittent JTAG with MaxV Device

I am fairly new into JTAG programming of devices. I have a new design with a MaxV CPLD. The first run of prototypes we had forgot the pullup/down resistors in the JTAG chain. After adding those...
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Altera_Forum
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14 years ago

Failure in the middle of JTAG programming doesn't sound like unknown initial JTAG state. It's rather a problem of JTAG signal quality or possibly bad power supply. If no external signals are present in the cicruit that may interfer with JTAG action, I would primarly think of distorted JTAG signals, e.g. ringing SCK.