| Trying to program ROM code into a several UV erasable ST M27C256B chips. Programmer is a GQ-3X Re-1.00. I select the exact chip type, blank check, load the bin file and program. Every 128th byte does not program. In other words, $7F, $FF, $17F, $1FF, etc, are unprogrammed (data value = $FF). The only exception is the LAST byte in the buffer, $7FFF, which programs fine.
This seems to only happen with ST M27C256B devices. I tested programming the same BIN file into a TI TMS27C256 and a Microchip 27HC256 and both programmed just fine. I have tried programming 6 different ST devices, 4 of which were brand new from the manufacturer. All had the same problem. I have also tried lowering the speed, doing a double write, and changing devices to the generic 27C256. Each time the results are the same - I cannot program the ST devices.