Taking a blank AT17LV010A(unprogrammed part), the for bytes of the register at x020000 is x00 00 00 00 which is the wrong reset polarity for Xilinx programming.
1. Boot GQ USB software, select AT17LV010A.
2. Set device offset x020000.
3. Click Read and the buffer fills with all 00 throughout the 1Mbit page.
4. With no other changes, click Read a second time, and the first 4 bytes show as x00 then the buffer fills with mostly xFF and few xC3 plus the device ID “1E F7” shows in a few places.
5. Now change first 4 bytes to xFF in the buffer, leaving the four or five bytes highlighted.
6. Click Write – this is very fast, just a second or two.
7. Now set device offset to x020001.
8. With no other changes, select Write again – This becomes a full write, but after about 5 seconds press CANCEL.
9. If you don’t press Cancel and the write runs to the end, the GQ USB software crashes. If it does crash, hit end program then restart GQ USB then reselect the device.
10. IMPORTANT: Remove part from socket then reinstall to power cycle the target chip.
11. Set the Device Offset to x000000 if it’s not already set.
12. Load latest .s file (MOTO S format HEX file).
13. Click Write to program and verify.
14. Now the part is ready for use.
Page 7 of the Application Note (AT17LV(A) Series FPGA Configuration Memory) file shows the Atmel steps to programming the Reset polarity. Using the Device Offset and the Read Buffer is an easy way to get to the locations we need to see. However, if we write the four bytes at x020000-x020003 once, it doesn’t change. Simply writing the same buffer to 0x020001 seems to miraculously solve the issue. Then we have to reset the Device Offset to x000000 and write the full program. Now the FPGA loads correctly.
BTW, if we set the device offset to x040000 and select read, the first bytes always show the correct Device ID. The Device ID feature of GQ USB does not work.
Thanks to Ron Lavallee for sharing this information.
Application Note:
https://www.mcumall.com/support/AT17LVSeriesFPGAConfigurationMemory.pdf
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AT17LV010A Register Programming Workaround
Posted - 06/06/2024 : 14:00:47
