The mistery of the PS/1 2121’s (S)VGA

Working on the 2121 support in IBMulator, I started looking for any kind of information about the video interface.

According to IBM Corp., the PS/1 2121 has got a standard VGA with 256KB of memory, very much like the 2011’s one.

Actually, the chip used is the IBM 84F7985 / TI CF62011BPC. Unfortunately there’s no datasheet and information is very scarce (if you have any technical info please let me know!)

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PS/1 2133 US preloaded software

A reader of this blog has kindly donated the US version of the preloaded software for the PS/1 types 2133 and 2155 models in the Fall 1992 product line (ISA board). – Recovery floppy images – same software but as extracted files

Software included:

  • IBM DOS 5.0
  • MS Windows 3.1
  • MS Works for Windows
  • PS/1 tools
  • PS/1 welcome
  • Recovery program
  • Video drivers (CL-5410, ET-4000)
  • Prodigy
  • Promenade

Thanks Ryan!

PS/1 2133 IT preloaded software

PS/1 2133 welcome

The Windows welcome screen

I recently won an eBay auction for a PS/1 type 2133 model 451 (EMEA market, roughly equivalent to the US model S48) with a 486SX-25 (with FPU/Overdrive socket), 2MB RAM, 85MB HDD, and an integrated VLB Cirrus Logic GD-5426.

To my great surprise inside the puny hard drive I found a complete backup of the original preloaded software (which I obviously used to restore my machine to the factory conditions).

So here it is in all its glory (it’s italian software, sorry non-italian speakers…): – IBM PS/1 2133 HDD files Italian version

The same set of programs was probably used for all the other models in the same spring 1993 product line, type 2155 included. But I’m not sure about this so if you have more info please let me know.

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IBMulator 0.7

A new version of IBMulator, the PS/1 emulator, is finally ready. In version 0.7 you’ll get:

  1. Better emulation of HDD and FDD with more realistic timings.
  2. Sound FX for FDD, HDD and the system unit.
  3. Various bug fixes.


The configuration file (ibmulator.ini) has changed so, if you are upgrading, delete or rename the old one to recreate.

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