S-100 Mini Front Panel

Post era Mini Front Panel

Don Caprio, among others, have created this Mini Imsai front panel clone. Shown here is my build of a revision F pictured here in a California Computer Systems with the front blank plate removed.

Resources

• Main documentation site with build instructions, schematics and parts lists
• You may be able to purchase blank PCB and other parts here check inventory.

Errata

Apparently C81 on the PCB is not connected. No need to fill.

Inconsistencies

The board seems to work pretty solid, and consistently for me - when it works. However I've noticed one anomaly with the sense switches / programmed output. Note that the image shown above is running the standard Imsai "Test Program 1" in a California Computer Systems chassis, Imsai 8080 CPU, Vector Graphic 8k static ram rev 1. Martin Eberhards 88-2SIOJP EPROM monitor, serial card too although I'm not using the monitor in this instance.

I have two Imsai MPU cards. They both work as expected in Imsai and Wameco front panels, however on this mini FP they both work however with one running it doesn't display the state of all the sense switches while the other does. If I put those same MPUs in the Wameco and an Imsai front panel they both work as expected. In the picture above you'll note that bits 0 - 3 aren't accurately reflecting the sense switches.

; Imsai Test Program 1

                START:
 0000           		org			
                LOOP:
 0000 DBFF      		in		0FFh
 0002 D3FF      		out		0FFh
 0004 C30000    		jmp		LOOP
 0007                   end