First, do a search on this. This operation has a few different methods that have been proven successful and both of them have been discussed often....
But the two methods are: set the start address to 04000 and the end address to 07FFF and then burn the 16k bin onto the 256k EEPROM and it should put the information into the upper half of the PROM where it needs to be. The other method is to go into DOS and use the copy function to take a 16k 00 bin file, and your 16k bin file, and combine them to make a 32k bin file that has 16k worth of 00 in the lower half of the memory addresses (FFs should also work) of the 256k PROM, and your data in the upper 16k. You will need a 16k bin file of 00s which I can email you if you cannot find....
Once in DOS, get to whatever drive your bin files are in and type:
copy /b 16k-00.bin+your.bin=your32k.bin
And plug in the proper names for each file that you are using.
Theoretically if you burn the entire AT29C256 EEPROM with a full 00 (fill the buffer with 00 (or FFs should work as well) and program the entire PROM), then modify the addresses to get only the upper half (as described above) and burn your 16k bin, it should do the same thing and get the information into the upper half of the PROM, leaving the lower half empty, but I haven't tried that particular method. I am having flawless results now with the copy method so I am not going to fix something that isn't broken....
Once again, do a search on this and you will find all of the information needed.
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1987 GTA L98 MD8
355, TFS Heads, LT4 Hot Cam
My GTA The Minnesota F-body Club 
