Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
11 years ago

EP3C16E144 JTAG and AS problem!

The JTAG chain can't be find, but the AS configuration is successful, why? MSEL1 is connected to 2.5V directly, MSEL0 and MSEL2 to GND. nCE is connected to GND directly. TCK is pull down wi...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
11 years ago

--- Quote Start ---

It all sounds correct. Whilst you've specified the rail sequence Cyclone III will tolerate the rails coming up in any order. So, I can only suggest a build or design fault.

Are you happy all the power and ground pins are connected? You mention the thermal pad - are you happy that's soldered correctly. Cyclone III devices don't work correctly without this pad connected. See this recent thread that discusses it: problem with jtag configuration cyclone iii (http://www.alteraforum.com/forum/showthread.php?t=46656).

Cheers,

Alex

--- Quote End ---

There has a hole at the bottom of the device on the board, i think i did solder it well, for the .pof file being programmed to the EPCS4 successfully at AS mode, and it also run well after power up.

Unfortunately, the AS mode can not be programmed now, i doubt the noise of the power circuit has completely damage the configuration function of this FPGA, but unexplained.