I have a brand new batch of 39SF040 chips from Mouser. Most of the chips (7 out of 10) fail when writing using my GQ-4x4. They all fail at the same address every time: Write failed, Address=0x01546D, Buffer=0x80 Device=0xC0.
I'm experienced burning flash chips and I've tried all of the usual troubleshooting methods/handling precautions I know of. I'm hoping I missed something and someone can help me out.
It seems unlikely that 7/10 chips would be bad straight from the manufacturer but that's a possibility. I'm wondering if there's a problem with my GQ-4x4, though it does seem to be writing 27C040s just fine, plus I burned an old 39SF040 from an different batch about 10 times over the past two days without issue.
There does indeed appear to be some kind of incompatibility. I was able to complete the writing process at -2 speed but verify fails and there are errors when doing a parity check on the data. I also receive occasional errors when trying to erase the chip, which I hadn't seen before, but it doesn't happen every time I try to erase.
I will try contacting support and hope this chip can work with the GQ-4x4. Thanks for your help.