Philcogrump
Experienced Member
I have this simple 8085A computer made by EKI, Inc. with a hexadecimal keypad and a row of eight LEDs for binary output. There used to be two 7-segment displays next to the LEDs, but I ripped them out because certain segments were shorted. Anyway, I believe this thing drives eight relays and the memory works (RAM is a 8155 if I remember correctly which is a RAM and I/O chip in one). With my knowledge on computers, I think the display uses shift registers to shift the numbers to the next available display when a key is pressed (ie. 53 in binary on the LEDs, if you press key D, then the display shows 3D, key A pressed then display is DA and so on). I have verified that the memory works by selecting an address location, storing a number, and recalling it back. However, that is what this thing does in program position, if I slide it in RUN, it pretty much does nothing and I have a list of 8085A opcodes, but I have no clue how to make something work and see an action. I have some pictures here:
http://members.aol.com/philcogrump/temp/
The pictures are eki1.jpg, eki2.jpg, eki3.jpg, and eki4.jpg. There are three red buttons on the controller board for address, write, and read. There is a switch on the processor board for program and run. Often, when it is in run mode, all LEDs light up and nothing much. Any ideas what this thing is and/or how to work it?
http://members.aol.com/philcogrump/temp/
The pictures are eki1.jpg, eki2.jpg, eki3.jpg, and eki4.jpg. There are three red buttons on the controller board for address, write, and read. There is a switch on the processor board for program and run. Often, when it is in run mode, all LEDs light up and nothing much. Any ideas what this thing is and/or how to work it?