Rich kids are into COBOL
elson at pico-systems.com
Sun Mar 1 15:39:04 CST 2015
On 03/01/2015 11:59 AM, Al Kossow wrote:
> On 3/1/15 3:42 AM, Johnny Billquist wrote:
>> The SKIP paradigm isn't so bad, in my mind.
> It makes sense on machines with a single word order code.
> Incr instruction
> pointer by one and you're done. It makes much less sense
> on multi-word order
> codes where you have to crack the instruction to see how
> far to advance the
> instruction pointer.
Oh, I KNOW why they did it, it was a VERY simple operation
to wire up
in the control logic of the CPU. But, I really like the
instruction layout of
the PDP-11, which was a VERY different paradigm, entirely!
On the PDP-5/8 and the -7, I am guessing they DON'T incr the
extra time, they set up for increment through the main
adder, and then
make a carry-in if they want to double-increment the PC.
More information about the cctalk