[Info-vax] OT: PDP-11 history in arstechnica

[gah4]

On Monday, March 14, 2022 at 7:18:27 PM UTC-7, Rich Alderson wrote:
> 
(snip of DEC syntax)

> "DEC" syntax, hmm? Macro-10: 
 
> MOVE 17,SUMWHR 
> ADDI 17,37 
> MOVEM 17,ELSWHR 
 
> The "destination" AC always follows the opcode immediately, the effective 
> address of the "source" comes after the comma. Note that since there are 
> "to-memory" instructions, the notion of "source" vs. "destination" is not 
> particularly useful... 
 
For IBM S/360 and successors, it is right to left, except for store instuctions,
which usually (or always) have opcodes starting with ST.  That makes them
easy to recognize.

PDP-10 "to-memory" instructions are not so easy to recognize.