This archive contains the source code for the 3 IBM PC BIOSs, the 3 IBM PC XT BIOSs, the IBM PC XT286 BIOS, and the 3 IBM PC AT BIOSs. It also includes the tools and batch files to make and verify all 10 versions of the BIOS. The tools include the current MASM 6.15/Link 5.0 and the Intel MDS programs ASM86i32, lnk86i31 and loc86i25. Also some tools to handle AOMF to BIN conversion and creation of ROM images. This builds files byte-for-byte compatible with the original files.
IBM PC BIOS
This archive contains the source code for the IBM PCDOS V2.11. This code was created
by disassembly of PCDOS V2.11 and merging the comments, structures, and labels from
MSDOS 2.0. This source code also contains the old instructions emitted by the older
assemblers. It builds with MASM615 and link50 from the bin directory in the BIOS
archive above. This builds files byte-for-byte compatible with the original files.
MASM615 target.asm,,,;
LINK50 target.obj,,,;
Compare target.EXE without header to target.COM file in each directory.
IBM PC V2.11 BOOT.COM
IBM PC V2.11 IBMBIO.COM
IBM PC V2.11 IBMDOS.COM
The following are the references for the IBM PC series of systems. I have collected these over the years from various sources.
Bill
Last Updated: 21 March 2022