JTag Chain

[Altera_Forum]

Hi all, 

I've been using Altera Cyclone EP1C12Q240C8 for my academic project. My computer doesn't detect the ByteBlaster II cable which I'm using. Few days ago I just disconnected the entire kit from my computer(as I was away) and reconnected it(after returning). When I try to program a .sof file it, Quartus gives an error message telling that it couldn't find any JTag Chain.:confused: The exact error is as given below..  Error: Can't access JTAG Chain Error: Operation Failed

[Altera_Forum]

The problem is in the connection with the board or a hardware problem on the board itself. Check the power supply voltages on the board and that the JTAG pins of the FPGA have a good connection with the JTAG pins of the connector.

[Altera_Forum]

Not detecting the Byteblaster or the JTAG chain are different errors with different causes. Although a Byteblaster has only a simple identification mechanism by feeding back a port bit, you should first check if the Byteblaster can be seen. Otherwise a PC or driver problem should be assumed.

[Altera_Forum]

Thank u guyzz!! But I rechecked all the power supply connections as well as the system drivers. I even tried using the FPGA kit with different computers. No Luck again. Might the hardware be crashed? Do I need to replace the ByteBlasterII Cable? Any help in this regard would be heavily appreciated..:confused:

[Altera_Forum]

If you have any other board with an Altera FPGA you may try to program it using the same ByteBlaster cable. If it works, the problem is certainly in your board. If it does not work, most probably the problem is in the ByteBlaster cable. 

At the moment I haven't got more clues...  Cheers. OD

[Altera_Forum]

Thanks a ton Orchestra! I don't think I have another FPGA kit. FPGA is quite ok as I see an orange light glowing when power is supplied to it. Well my presumptions about it being alright might be pretty naive. Even then I guess my FPGA is quite fine. 

Will check it out soon.  Thanks again!

[Altera_Forum]

Checked it just now. I inverted the ByteBlaster II Cable plug. Even then the results are so indifferent. I think the cable is screwed. I see FPGA's Orange LED glowing. Does it indicate that the FPGA is quite fine?

[Altera_Forum]

What is the meaning of that orange LED? It maybe linked to a previous code which was prgrammed in the past (maybe by someone else) and resident in a flash memory in your board. So, at power up, the FPGA starts working with the previous design and you are no more able to reprogram it because of the interruption of the JTAG chain.