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Altera_Forum
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12 years ago

JTAG Configuration - conf_done pin always low, even pull-up

After Board power-on, the conf_done pin which is also 10k pulled-up to 3.2V, but the pin is stick to low. the pull-up is not working for this pin. No short to GND. After power-on device, 16...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

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I'm just shooting in the dark, but are the M0,1,2 pins connected correctly? Does your device have an exposed pad on the bottom? Are you sure it's connected to gnd?

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>>

M0,1,2,0 is set to "0000" and sure it is not short to gnd. you means the conf_done pin is open?

hwo to check?

Jtag chain debugger has detected lots of fpga , even using one fpga.

Assumed the pull-up failure of conf_done pin cause the multi device detectd over jtag chain