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Altera_Forum
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13 years ago

JTAG Chain problem - no device detected (Tried with multiple boards)

Hi everyone, I'm doing some work with custom cyclone III boards and am in the process of trying to program the device using a JTAG port and a USB Blaster cable. The boards were used last yea...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

I would recommend attaching the scope to the lines, setting a trigger level of about half the peak voltage (maybe 1.2v depending on what sort of logic you're driving) and running `jtagconfig` from the command line.

If you have a two channel scope then once you have one of the signals running you can trigger off that one and measure them both. All four signals should be changing during the jtagconfig scans.