CMOS battery replacement

Dallas DS1287

I received a couple of requests recently about the Model 2011’s RTC battery and how to replace it.

So I quickly arranged a mini how-to to explain the process.

How to replace the CMOS battery

Hope this helps.

PS/1 2123 ROM BIOS and starter diskette

A couple of great additions for the Downloads section: the ROM BIOS and the starter diskette for the IBM PS/1 386SX Model 2123.

PS1_2123_87F4794_ROM.zip – ROM BIOS, P/N 87F4794, dated 1992
PS1_2123STRT.zip – Bootable Starter Diskette with diagnostics software.

Note: the file 2123STRT.DSK inside the starter diskette archive is a stardard floppy image so you can use it with your preferred image transfer program.

Thanks Leo for the donation!

PS/1 2155-78C US preloaded software

Another donation: the preloaded software of the PS/1 2155-78C, US version.
The PS/1 2155-78C was a multimedia machine released in the US market during the spring of 1994 and equipped with:

• Intel 486SX2/50
• Cirrus Logic CL-5428 1MB VLB
• 253MB HDD
• 4MB RAM
• Matsushita 2x CD-ROM drive
• Creative Sound Blaster 16
• Modem 2400 bps

PS1_2155-78C_Spring94_HDD_Recovery_US.zip – HDD software as a recovery set (floppy images)
PS1_2155-78C_Spring94_HDD_Files_US.zip – HDD software as simple files

Software included:

• MS-DOS 6.21
• MS Windows 3.1
• MS Works for Windows 3.0
• PS/1 tools, welcome
• Prodigy
• America Online
• Photo Gallery
• Co/Session
• Sound Blaster 16 audio drivers and software
• Cirrus Logic GD542x video drivers

Thanks Austin!

PS/1 2123 US preloaded software

Thanks to a donation I can share with you all the US version of the preloaded software for the PS/1 model 2123 (Spring 1992)

PS1_2123_Spring92_HDD_Files_US.zip
PS1_2123_Spring92_HDD_Recovery_US.zip (same software but as recovery floppy images.)

Software included:

• IBM DOS 5.0
• MS Windows 3.0
• MS Productivity Pack for Windows
• MS Works 2.0 for DOS

Thanks Ryan! (again)

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!)

PS/1 2011 UK ROM

Thanks to a generous reader of this site, I finally got hold of the UK version of the IBM PS/1 model 2011 ROM.

PS1_2011_ROM_UK.zip

IBMulator 0.8

I’ve deemed the source code stable enough to tag and release a new version with:

• AdLib emulation
• Faster CPU emulation (50% faster!)
• Various bugs fixed especially in the audio subsystem

Download IBMulator 0.8

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