New Contributor
Hi lixy,
The board isn't the evaluation kit from Altera, it was designed by someone else. Thank you for your response, it turns out that the FPGA was dead. I had it replaced and everything works again.
Best regards,
Super ContributorHi,
I wonder why TDO shows only 1 V output level. The signal won't be recognized by USB Blaster running with 3 or 3.3V Vcc,target.
There are several possible reasons why TDO voltage is too low
- damaged FPGA TDO pin
- additional component at TDO node i sshorting output
- USB Blaster defect, apparently excluded by testing with different devices
Regards
Frank
New ContributorHi FvM,
I was also wondering if the 1 V output level was normal for this board. We solved this problem replacing the FPGA. After replacing it I still got 1 V output for TDO and I was able to program the FPGA so I'm assuming it is "normal" for this board, something at the node is probably shorting the output (which I know is not ideal). Thank you for your response.
Regards,
Super ContributorHi,
1V TDO level isn't normal because it's not necessarily recognized as high by programming adapter with Vcc,target of 3 or 3.3V which requires 2.0 V Vih.
Can you tell the board type?
New ContributorHi,
Unfortunately the board was designed by someone else and I don't have a lot of details about it more than the printout. However, the problem is solved for now and I will take this problem into account for future versions of the board.
