MMRCCMid-Michigan Retro Computer Club

DIR PROJECTS

Member projects

The next thing on the workbench.

Old hardware. New ideas. A place for the things our members are building, restoring, and figuring out.

bAIos on GitHub
Illustrative retro workbench with a CRT displaying the bAIos project name. This is not a screenshot of the firmware.

Firmware / 386 & 486 / by calculatetech

bAIos

Experimental

From the workbench

A new BIOS for old machines. Experimental replacement firmware for selected 386- and 486-era PCs.

bAIos combines shared firmware services with board-specific chipset, cache, and controller initialization. The project focuses on reliable startup, useful diagnostics, configurable memory timings, and compatibility with real DOS software.

Documented ports

Compaq Presario 800
Original implementation and behavior baseline.
Mitsubishi MP386/25
Physically tested port with expansion RAM, cache, and timing controls.
Packard Bell PB430
Physically tested development port with timing and cache controls.
PC-Chips M919
Experimental port; physical cache stability remains unresolved.

Follow the project

Source repository Read the code and follow development.Project README Scope, setup, ports, and known limits.Club discussion Bring your questions to the group.

Experimental firmware for specific hardware. Read the selected port’s documentation before building or flashing. Source checks and emulator tests do not establish hardware stability.

Source: bAIos public README · Checked October 26, 2026.

What’s taking up your workbench?

A restoration log, a hardware mod, or a late-night coding rabbit hole? Share it with the club on Facebook if you’d like it featured here.

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