How do you access this flash? By a CPU? What type?
It could be possible that you have an address change during the WR/CS
pulse or a spike on your VCC line. Do you have decoupling capacitors?
hello,
can you read any data? do you have two flash devices in parallel to reach 16bit bus-with. then you have to be care for the adresses you send to the flash (you have to double the adresses).
if you have an logic analyzer, check wether the cpu sends the correct unlock cycles (if you want to read device id or during programing).
Check (with oscilloscope or logic-analyzer) if the setup and holdtimes
are met. Probably there is a problem with the propagation-time inside
your address-decoder.