==================================================================================== IBM 5150 BIOS - USE OF A 27128 EPROM VIA 27xxx ADAPTER ==================================================================================== The 27128 (or 27C128) EPROM is 16 KB sized. So, for the 27128 (in a suitable adapter), what we will do is double up the 5150's 8 KB sized BIOS image, to get a 16 KB sized image. +-----------------+ | 8 KB SIZED BIOS | +-----------------+ | 8 KB SIZED BIOS | +-----------------+ In Windows, we can do the doubling up via a command window. The following assumes that the file containing the 8 KB sized BIOS image is named SOURCE.BIN STEP 1: Open up a command window. STEP 2. Change to the drive/folder that contains SOURCE.BIN STEP 3. Enter in the following command: COPY SOURCE.BIN /B + SOURCE.BIN /B TARGET.BIN /B The file TARGET.BIN has been created. Use that 16 KB sized file to populate your 27128 (or 27C128).