While programming a stratix V fpga (using JTAG) the board was unintentionally power cycled. Now it is no longer possible to access the device using the programmer. Message is 'Can`t access JTAG chain'. Is there any way to recover the device?
There are couple things you can try to do:
1.You may a receive this error message during auto-detect possibilty due to a download cable problem, TDO is not connected properly, a noisy TCK signal, or TDI shorted to GND.
Here are some suggested steps for resolving the issue:
- Make sure the pull-up and pull-down resistors connected to the JTAG pins are following the recommended values as stated in the respective device handbook.
- Check the JTAG chain connectivity and the integrity of the TCK signal. Intel recommends pulling the TCK pin low through a pull-down resistor. Also make sure the TCK signal is clean to avoid any programming or JTAG configuration failure.
- Use another USB-Blaster or other download cable. This is to ensure that the download cable is functioning.
- Check the voltage seen on the pins of the JTAG header to see if they are at appropriate levels. The download cable is powered by the board, so ensure your board is properly powered.
- Ensure all power supplies to the device are within recommended operating conditions. Refer to the respective device handbook for the correct voltage level.
2.Which USB blaster you are using? Is it USB blaster I or USB blaster II?
if you are using USB blaster II, maybe you can try to reduce your TCK value.
3.You can try to used JTAG Debugger tools to check this issue further.
Thanks for your feedback.
So you think it is not an issue the fpga did not complete a programming cycle due to the power cycle of the board?
The USB blaster (RevC) cable is ok on other device (same type, same board type) however not on this specific device/board that had a power down/up during programming.