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ROM from LOMAS 286

new_castle_j

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I'm doing research on a LOMAS Lightning 286 S-100 board. The documentation is very scarce, but from what I can gather, there was an optional ROM for this board that is supposed to "emulate the functions of the PC-ROM BIOS" I'm curious if anyone here can take a look at the dump of my ROM and quickly determine if it resembles a PC BIOS. If it is a PC look-alike, does it also support a BIOS expansion feature, where I might be able to use INT 13 boot support for a hard disk? Thank You! Link below if anybody has interest.

 
It appears to be doing some PC-like things (read/write BIOS data area, CGA graphics, etc.) but it doesn't have any of the fixed offsets necessary for a "100% PC-compatible" BIOS. For example, the 8x8 font is at offset 16F1 when it should be at 1A6E. I don't see any checks for the option ROM signature 55AA. That pattern is only used for the memory test.

There is code to read the boot sector from the floppy and jump to 0000:7C00, so it should boot DOS.
 
I'm doing research on a LOMAS Lightning 286 S-100 board. The documentation is very scarce, but from what I can gather, there was an optional ROM for this board that is supposed to "emulate the functions of the PC-ROM BIOS" I'm curious if anyone here can take a look at the dump of my ROM and quickly determine if it resembles a PC BIOS. If it is a PC look-alike, does it also support a BIOS expansion feature, where I might be able to use INT 13 boot support for a hard disk? Thank You! Link below if anybody has interest.

You may have already found this manual, but it provides a good description of the Lomas S100 hardware required to run a system capable of emulating a PC and the capabilities of the ROM BIOS provided by Lomas to run MS-DOS:

This optional ROM was provided to people who purchased a Lomas CPU board along with the Lomas "Color Magic" board. Having the "Color Magic" board was essential for running MS-DOS on a Lomas S-100 based system - that one board provided the functions of an IBM-PC color graphics board, keyboard interface, timer interrupts, and speaker. The Lomas ROM BIOS also supported their own S100 floppy disk controller.

For a description of how Lomas supported a hard drive with their systems (which apparently required another version of the ROM BIOS provided by Lomas) see the article titled "SCSI for the S-100 Bus" here:
 
Thank you both for your insights into my ROM and system. It sounds like I may have the Lightning 286 and ROM that is meant to be paired with a ColorMagic board for running DOS, that's exciting! It's been very difficult finding information on LOMAS, but I'm doing my best to put the pieces back together. Along with this 286 board, there is also a ColorMagic board, a Lomas Floppy board, MegaRAM Memory, and Lomas SCSI board in my pile of Lomas hardware.

I read the Aug 1988 Computer Journal article about the Lomas SCSI... very helpful thank you! That article puts a few things into place. The Lomas SCSI board doesn't have a ROM on it, and since there's no option ROM signature 55AA found in the ROM, this system must not work like a PC where you can extend the BIOS. Perhaps the ROM I have already supports the SCSI board, that would be ideal!
 
I'm attaching a snip from an article of Z100Lifeline that I found, issue #87, June 2003. It talks about a DOS SCSI driver that was created for the Lomas SCSI card to be used in a Zenith Z-100. If anyone has any copies of the LDP version of this software, I'm very interested. The programs I'm interested in would be named LDPSETUP.COM LDPSCSI.SYS LDPINFO.COM LDPDUMP.EXE and LDPDFLS.COM It's a long shot, but all the more rewarding when lost treasure is found, Thank You!
 

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