Can not Download by Jtag!!!! IMPact hint that...

[vvsvv]

"
ERROR:iMPACT:583 - '1': The idcode read from the device does not match the idcode in the bsdl File.
INFO:iMPACT:1578 - '1': Device IDCODE :
00000000000000000000000000000000
INFO:iMPACT:1579 - '1': Expected IDCODE:

000011000010100000010010011
"

How to deal with this error !!!
Please help me !!!

however , yesterday the system can download program by JTAG !!!
the FPGA is spartan2, xc2s100.

Please help me!!

 

[zcq]

Did you pull-up tdo?

 

[shawndaking]

1 CheckOut You'r JTAG Cable Connections !!!

2 Also Have Latest Impact Versions.

3 Check That Your PC iS ok.

 

[Jackwang]

I think you should consider some question as follows:
1 download mode is identical to hardware design.
2 cable connections is all right.
3 create download file, assure you choose the xc2s100.
4 power is normal.
5 refer to datasheet, assure your design is right.