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altair8800_ALPHA

ABabu_developer•Created December 19, 2011
altair8800_ALPHA
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Description

***ALPHA software*** You have been warned! Right now, the only thing that works is the front panel switches, and leds. The original would have only had red leds, but I thought it would be fun to have other colours. At this point, there is a kind of pattern to just play with lights. When I get the CPU written, I will see about writing the 8080 code to replicate the light flashing stuff. HOW TO USE THIS: Using this is going to be a lot of work. You program this by flipping the switches to handcode every instruction byte in 8080 machine code, just like the original. To program the memory of the computer: 1) turn the on/off switch to "ON" 2) turn the stop/run switch to "STOP" 3) turn the protect/unprotect switch to "UNPROTECT" 4) set the 16 bit memory location using the sixteen "Sense switches". I recommend starting with "000000" (Octal) "0000000000000000" (Binary) 5) toggle the EXAMINE button 6) set the 8 bit data value you wish to program into memory using switches "7-0" 7) toggle the DEPOSIT switch 8) set the next 8 bit data value 9) toggle the DEPOSIT NEXT switch The program will not run until I get the CPU programmed. I am going to program the CPU to act like an Intel 8080 CPU, just like the original Altair 8800. For more info on Altair 8800, check out: http://oldcomputers.net/altair.html To get some perspective, the original had a whopping 256 Bytes of RAM, expandable to a maximum of 64K. I use the value of 256 for the "maximumMemory" This is set in the" Stage" script when the "green flag" is clicked. WHY I MADE THIS: I got my inspiration for this when I was thinking about a computer I had designed and buile by hand soldering hundreds of wires. This computer made use of the 6502 chip and a bunch of other chips from different computer architectures that I liked. I had given the whole mess away when I was single, now I lament that decision because I'm married now and have two boys who would have really appreciated the old beast I had made. Alas, I don't even have a picture of it. This project is further inspired by the original Altair 8800 which was the first "home computer" on the USA market back in 1975.

Project Details

Project ID2226920
CreatedDecember 19, 2011
Last ModifiedDecember 19, 2011
SharedDecember 19, 2011
Visibilityvisible
CommentsAllowed