Intel iSBC 80/24 System

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This is a new page covering the iSBC 80/24 Single Board Computer (SBC).

This board was introduced in 1985? provide OEMs with an SBC to begin building systems and applications using the 8085 processor. It was used with additional boards from Intel to expand memory and I/O capabilities.

Technical References

iSBC-80/24 Single Board Computers:

iSBC 80/24A Single Board Computer Hardware Reference Manual May 85 148437-001

Additional boards to make a complete system:

iSBC 32/48/64K RAM Board Hardware Reference Manual Jan 79 9800488B
iSBC 202 Double-Density Floppy Disk Controller Hardware Reference Manual 77 9800420A

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Monitor Source Code

Mon80p Ver 1.1 for iSBC 80/24 [1 Nov 1976]
iSBC 930 Monitor (MON830) for iSBC 80/30 Manual [24 Apr 78]
Port of iSBC 930 Monitor for iSBC 80/30 with Modified Commands [2016]

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Operating Systems

These Intel SBCs would not run the Intel MDS OS nor the ISIS-II OS. It would require special versions of these to run modified for the I/O port assignments. This board has a modification to disable the onboard ROM and RAM. The ROM maps at address 0H which has to be RAM for any of the OSs to operate. The RAM has to be disabled because it overlays external RAM, and the external RAM is the only RAM available for DMA operations from the disk controller boards.

This board had a version of CP/M-80 ported to it utilizing an iSBX-218A Floppy Disk Controller. I have yet to get this version of CP/M to boot in this configuration. Here is what I have done so far:

CP/M-80 V2.2 Source for Intel System 80/24

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Last updated: 16 September 2017