Posted By
JamesC
on 2014-11-15
14:40:01
|  Re: 1541-II drive memory test
Same reason a 64+1540 don't get along, or why the 128 can't do 40 columns in fast mode -- incompatible clock rates.
16 and Plus/4's BASIC runs slower than the 64's BASIC. 128 in 40 column mode is even slower. If you want to test the difference, try these one-liners:
Screen on, all machines: TI$="000000": FOR X=1 TO 10000: NEXT: PRINT TI/60
Screen off, 64/128 40 col: P=PEEK(53265):POKE53265,11:TI$="000000":FORX=1TO10000:NEXT:?TI/60:POKE53265,P
Screen off, 16: P=PEEK(65286):POKE65286,11:TI$="000000":FORX=1TO10000:NEXT:?TI/60:POKE65286,P
Screen off, 128 2MHz: FAST:TI$="000000":FORX=1TO10000:NEXT:?TI/60:SLOW
On YAPE, screen on takes 14.966 seconds, screen off takes 8.766 seconds. That's a 41% speed increase ... speed that we can use to keep up with the disk drive. 
|
