So I had this last two days a weird issue with both Nano 9k and Nano 20k.

After flashing Nano 20k and testing my changes, I did some changes and when trying to program the flash I got the issue error GOWIN device not found. So I decided to disconnect the USB cable, reconnect and try again. Same issue. I tried instead of writing to Flash, to write to RAM. Same issue. Tried educational programmer, same. Tried all clock speeds, same issue. GW2AR is still running the last bitstream I burned into flash, but it seems that BL616 can't see it tho.

https://preview.redd.it/tqixebp7rttc1.png?width=625&format=png&auto=webp&s=ed95d22d3750abc20df896e042993e7caeef6710

Now, today the same thing happened with Nano 9k. So I guess my laptop might have something to do with that. 9k doesn't seem to be running any code from flash though.

I guess it has something to do with BL616 but I don't know what exactly it can be. Anyone had this issue before? Any chance there's a binary for BL616 that I could try to flash for 9k or 20k? Otherwise I'll have to prepare a nice funeral for both of them 💀

Edit 20240411: I know about Tang-Nano-Doc/questions.html. Their solution in 1.7 is to use the latest programmer, I'm using GOWING IDE v1.9.9 and there's absolutely no improvement. I'm also aware about clock frequency, that doesn't change anything.

It might be realated to Dual-Purpose Pin Configuration, JTAG and RECONFIG_N pins particulartly, but Nano9k never changed those pins configuration:

https://preview.redd.it/ink1byyoqttc1.png?width=1119&format=png&auto=webp&s=4f2fd1afb05dd9f3b0f9374da01f7f1152ebae98

Nano20k changed MSPI but not JTAG nor RECONFIG_N:

https://preview.redd.it/n737qftsqttc1.png?width=1146&format=png&auto=webp&s=68332412349ead59b514343de1d35219fb29b7d8

Using OpenFPGALoader under W10 using WSL2 Ubuntu16.04.6 and usbidp shows TD0 is stuck at 0:

https://preview.redd.it/qqybb5s2rttc1.png?width=1083&format=png&auto=webp&s=33cdc9ec8a76d829344217822b46dd72ea0a7262

If the case is that JTAG pins are now missconfigured, I'll try using a RV-BL702 JTAG Debugger to see if with it I can access the Flash or SRAM again to try to recover from this huge fail :)

https://preview.redd.it/u0onq6dorttc1.png?width=1034&format=png&auto=webp&s=288898faabb910ee9bfc9ff783fb45a58d844efe

Edit 120240412:

Nano9k running hot in this area:

https://preview.redd.it/9qe8ay7a82uc1.jpg?width=323&format=pjpg&auto=webp&s=fde7b478cb11c9bedf10a31996d040a74ac4cd32

This solution for Nano9k says that pressing S2 before flashing should help (S1 according to schematic) but no changes.

https://preview.redd.it/mgstsqkj82uc1.png?width=2014&format=png&auto=webp&s=a042b5ad2af1c602c6878c8a9f7cbc3338f9766e