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SYiwe's avatar
SYiwe
Icon for Occasional Contributor rankOccasional Contributor
6 years ago

Cannot access the JTAG port of Arria10 SoC

There’re two Arria 10 SoCs in my design, the follwoing picture indicates the JTAG chain on board. Chip A and Chip B share the same TCK & TMS. TCK is pulled down to GND and TMS is pulled up to VCCP...
JohnT_Altera's avatar
JohnT_Altera
Icon for Regular Contributor rankRegular Contributor
6 years ago
This can happen if there is a corrupted bitstream. 1st method to resolved the issue is by changing the MSEL to not AS mode and power the board before switching the board back to AS mode. Then you can use JIC file to reconfigure it or erase the flash content. 2nd method is have a direct connection from the blaster to the flash through Active Serial interace. Then erase or re-program it.
SYiwe's avatar
SYiwe
Icon for Occasional Contributor rankOccasional Contributor
6 years ago

Thank you for your answer.

I changed the define of MSEL from 011(AS mode) to 000(JTAG mode), now nSTATUS pin is high, as well as nCONFIG.

But the programmer still reminds me "unable to scan device chain" as you can see in the following picture.

The oscilloscope can detect pulses on TDO pin when I click "auto detect".

Currently I prefer to access the device via JTAG rather than AS interface, so I hope to find a solution to access the JTAG chain.

Any suggestions?

Thanks, regards.