The S29GL512 has more than one problem I can not understand.
1: Low or High states of the WE CE OE pins in writing. 2: In the case of reading again the states of the 1 st posting pins. 3: To start the Write and Read routines, the appropriate CE CE OE pin is adequate. 0x0555, 0x0AAA in initialization routines if there is not enough I have a shortage of how to sort the initialization codes.
Could you please provide the full part number you are using? We have S29GL512S/T/P/N series of parallel NOR flash.
WE/CE/OE high/low state please reference the write timing picture from corresponding datasheet.
For the initialization code, we have the LLD for parallel NOR flash on our website which there is some basic code you can reference, the download link is on the "Software & Tools" tab of the following link: