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Altera_Forum
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16 years ago

Error in JTAG chain before reprogramming

I'm trying to reprogram a MAX II CPLD with USB Blaster in JTAG mode. When I click Auto Detect appears error message “Unable to scan device chain. Can’t scan JTAG chain.” Testing JTAG chain with...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

Besides powering the board I have connected pins 2 and 10 of the male header to ground, pin 4 at 3.3 V as indicated in the USB-Blaster Download Cable User Guide.

Routings for TCK, TDI, TMS were already drawn.

Process stops immediately so I can’t measure TCK, TDI, TDO signals. From oscilloscope I see only an initial transition when I press Start button in Quartus II Programmer. Then TCK remains low, TDI and TDO high.

Thanks ;)