February 1. 1994 The code is for Bios, or Bios and Mcode for your Adaptec SCSI hostadapter. The code is in binary format. The code must be programmed into a eprom with the same size. (i.e. 27C128, 27C256, 27C512) Check the current eprom size on the existing eproms (Bios, Mcode) On some hostadapters you will only find one eprom (Bios). The microcode is labeled with the word 'MCODE'. The bios is labeled with the word 'BIOS'. The MCODE and BIOS should only be changed together. Be sure to watch pin 1 orientation or the eprom, signified by a notch on the eprom and the eprom socket. This code is provided with no warranties expressed or implied. It may or may not improve performance/compatibility with your SCSI hostadapter.