TDO pin stuck at 1. What does it imply?

[walker_iit]

Hello,

I m presently debugging a custom built FPGA board, which i m trying to program using UrJTAG software. The software is capable of detecting the usb-jtag converting IC, ft2232, but when i give a detect command to detect the ALTERA Cyclone 4 FPGA in it, it gives a warning "TDO stuck at 1".
What does it actually imply, it was working properly two days ago, and i was atleast able to program something into the FPGA, but now this warning comes everytime i try to detect the chain. Does it tell me that there is any open connection between the ft2232 convertor output and the jtag pins of the fpga, or did the FPGA become faulty? Need help

Thanks in advance
Walker

 

[gongdori]

If there are multiple devices on the chain, make sure the chain is not broken. I don't recall if there is pull-up or pull-down (or nothing), but it should toggle when you use it.