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Altera_Forum
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15 years ago

EP2 won't AS configure, nCONFIG stuck lo

EP2C5Q208 will not AS configure itself. Circuit is exactly as Fig. 13-7, page 13-20 in Cyclone2 Device Handbook, Vol. 1 for a single device. Configuration device is EPCS4. (Using USB Blaster Quart...
Altera_Forum's avatar
Altera_Forum
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15 years ago

The fact that you are unable to configure through JTAG is a big red flag. Can you ID the cyclone device with the USB blaster or does that fail as well? If you can ID the device, but the programming fails, it may be due to a fault on nCONFIG. but if you can no ID the device at all, That usually is a power supply issue.

It looks like you have already checked your VCC IO's and VCCINT levels, but also make sure your VCCPLL's are ok On the Cyclone 2 device these should be filtered versions of the VCCINT 1.2V, but if you have mis-stuffed components, you may have an open there preventing configuration to start.

Pete

nCONFIG should have a pull-up on it. Make sure it's not shorted to ground somehow, This would prevent AS configuration, but not JTAG device id.

Let me know if you are able to r