Intel ISIS-II Operating Systems and CUSPs

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This is a new page covering my work with the ISIS-II Operating System.

Mark Ogden has reverse engineered most of V4.1 back into the PLM80 and ASM80 source files. These files will validate against the original ISIS-II V4.1 executable.

I have spent a lot of time disassembling these different versions of ISIS-II and the tools that that ran under it. I have generated a 7Z file which contains the tools, disk images, and configuration files to generate assembler source files for OS versions and tools listed below and validate the code generated at the binary level to the original binary code.

I hope to be able the generate the PLM80 source for all these versions but that takes a lot of time. I have used the tools and tricks than Mark uses but it is certainly not a complete solution. One could develop a program that would read in the assembler source and produce PLM80, but that would also take a great deal of work.

Current ISIS-II OS and CUSPs Disassembly

ISIS-II Disassembly Archive
ASM48 UPI41 V4.0 1980
ASM51 V2.0 1981
ASM51 V2.1 1983
ASM80 V3.0 1979
ASM80 V4.0 1980
ASM80 V4.1 1981
FORT80 V2.0 1978
FORT80 V2.1 1978
IPPS V1.4 1984
ISIS-II PROM Mapper V2.0 1978
ISIS-II PROM Mapper V2.1 1980
ISIS-II V4.2 (W) - For an iSBC-215G Winchester (ST-506) hard drive
ISIS-II V4.3 (W) - For an iSBC-215G Winchester (ST-506) hard drive
ISIS-II V4.3 (WSI) - For a SCSI/SASI interface board and hard drive
PLM80 V3.0 1976
PLM80 V4.0 1977
RL51 V3.0 1983
UTILS V2.2 1982 - contains OBJHEX V2.2 and HEXOBJ V2.2

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Last updated: 18 October 2017