Date: Mon, 18 Jan 93 06:53:54 EST
From: "Mark W. Eichin" <eichin AT cygnus DOT com>
To: bernd AT bwhwob DOT escape DOT de
Cc: djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: GAS vs. Intel.

>> From bernd AT bwhwob DOT escape DOT de (Bernd Wiegmann)
>> The Motorola mnemonic is called mov (for move) so the logical order
>> of the operands is from to. Zilog used the mnemonic LD (for load) and
>> the logical order is (load) arg (with) value. I think Intel should have
>> called it LD too to avois this kind of confusion.
	Intel, in this case, was first. The documentation for the 8080
(and earlier ones I suppose) described the operation of copying a
value from one 8-bit register to another as MOV (there was also LDA
for an 8 bit indirect load, and LXI for a register pair immediate load
(MVI was 8 bit immediate.)) The Zilog Z-80 processor was binary
upwards compatible with the 8080 - but apparently they felt that the
Intel *mnemonics* were protected (copyrighted, I think) and therefore
they had to produce something different (more regular and
comprehensible, in my mind, even though I learned 8080 mnemonics
first.)
	I don't recall what the motorola 6800 and 6502 mnemonics were,
though they did have a TX-something instruction (for Transfer, though
I think it swapped the values rather than copying.)

				_Mark_ <eichin AT athena DOT mit DOT edu>
				MIT Student Information Processing Board
				Cygnus Support <eichin AT cygnus DOT com>