I'm trying to program M27C160 EPROMs with the GQ4X4 and ADP-054. The chip seems to program normally (100% complete) but the verify fails with all "00"s in the original file being replaced by "FF"s on the chip. have set the correct voltages in devices.txt and verified there is minimal voltage drop on the USB port, I have also used an external power supply and tried programming at slower speeds. J1 on the ADP-054 is set to 1-2. I have four 27C160s and have the same problem with each. I just programmed several 27C322s with no issues so I don't think there's anything wrong with the hardware.
Here's the line in devices.txt
Name="M27C160",ID="XXXX",Class="27C800",VCC="5V",WVPP="12.7V",WVCC="6.5V",Category="EPROM",MFG="ST",CodeSize="2097152",Adapter="ADP-054 16 BIT EPROM ADAPTER";
Here's the error upon completion:
Here's the original file:
Here's the result of reading the programmed chip:
Any ideas? This is driving me nuts.