8080 Assembler-Text Editor (ATE)

Roy J. Tellason rtellason at blazenet.net
Mon Apr 17 15:59:31 CDT 2006

On Monday 17 April 2006 01:05 pm, Don Y wrote:
> > Does anyone remember the conflict between the MITS and IMSAI (actually,
> > the rest of the world) about using octal vs. hex representations of data?
> >  It's very obvious just by looking at the two systems--the Altair 8800
> > spaces the front panel toggles in groups of 3, whereas the IMSAI 8080
> > color-codes the switches in groups of 4.  I think that the early MITS
> > assembler used octal, although it's very hard to remember.
> When I was developing Z80-based products, an ongoing *battle*
> was the use of hex vs. "split octal" (e.g., 0xFFFF -> 0377 0377).
> The octal camp claimed the Z80 was an "octal machine" (oh, really?)
> and, for "proof", showed how so many of the opcodes could be
> committed to memory just my noting the source & destination
> register "codes" and packing them into an octal representation:
> xx xxx xxx  (of course, I wonder how well their argument would
> stand up if Zilog had opted to encode the register fields
> as:  xs dds dsx??  :> )

Hehe.  I remember that "big controversy",  dunno at this point if it was in 
some of the magazines or what.

Me,  I wish they'd made those common TTL 7-segment decoder/driver chips 
display something more like hex when you got into codes past 9...

> Octal?  Hex?  Just give me a symbolic debugger and let *it*
> keep track of these minutae...


> Ah for the days of toggling in bootstrap loaders with front
> panel switches.. :-/  (at least bigger machines treated octal
> as "real" octal and not this "spilt octal" nonsense...)

As did that H11 that I got to type in the boot loader any time I wanted to do 
something with it,  which I did indeed find exceedingly tedious.

Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space,  a critter that can
be killed but can't be tamed.  --Robert A. Heinlein, "The Puppet Masters"
Information is more dangerous than cannon to a society ruled by lies. --James 
M Dakin

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