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Hey Guys,

This is a hardware question, not directly related to the OS itself, if this isn't the right place, please direct me to where I should go.

I'm working on building an 8086 computer, I've figured out most of the chips, design, and all that, I've run into a bit of a speed bump though, I've been searching for BIOS ROM chip, and I might just not be searching for the right terms. Does anyone like say, intersil, or ti, etc, still manufacture bios chips that can be used with an 8086, if not, I'd also be okay with programming a rom with the bios code, if anyone knows a source with some old IBM rom codes, etc.

Any input would be great.

Thanks

Unless you're making an exact hardware clone of an existing 8086-based PC, you will need to write your own BIOS.

Is your computer supposed to be IBM PC compatible? If so, you can use old IBM manuals as a reference for what kind of functions your BIOS will need to perform. At minimum, you will need to implement most of the interrupts provided by the PC 5150 BIOS to boot MS-DOS.

Is your computer an original design not compatible with the IBM PC? If so, your BIOS can do whatever you want it to do. A typical BIOS will run some self-tests, then load software from a disk. It may also provide functions that can be called from the loaded software, such as keyboard input, display, or disk access.

You can find the technical reference manuals for the original PC and the XT on bitsavers. They contain complete BIOS listings.

A little Googling will reveal plenty of sources for a PC/XT BIOS. Here's just one: https://code.google.com/p/xtideuniversalbios/