8080 Assembler-Text Editor (ATE)

But the Z80 and the 8085 are both based on the 8080 architecture and instruction set - so much so that they will both run the vast majority of 8080 code. Is anyone really suggesting that it's an "accident" that the Z80 happens to run 8080 code ... or did Zilog begin with the 8080 instruction set definition (hence my point that they (Zilog) did not make the decision on the bit arrangements of the opcoodes). Doesn't this suggest that xxdddsss actually was *better* - since you took advantage of the alignment with octal notation to make it easier to hand-assemble... Thats my whole point. The fact that the instruction set happens to align well with Octal notation is the main reason that a lot of people used it. It's interesting to note that almost all of the Intel docs are in hex, or binary notations - but Mits, Heath and several others thought that Octal was a better fit. As noted earlier, I happen to be from the "hex" camp ... but I don't think it's fair to dismiss the octal guys as "nuts" ... the use of octal on the 8080 did have some benefit, and there were a lot of people who went that route - to ignore or discount this does not present an accurate depiction of the time period. Now why some people chose octal for other processors, which didn't have an architectural slant toward 8 is more of a mystery to me.... Dave -- dave06a (at) Dave Dunfield dunfield (dot) Firmware development services & tools: www.dunfield.com com Collector of vintage computing equipment: http://www.parse.com/~ddunfield/museum/index.html