Contributor: TERJE MATHISEN
{
From: terjem@hda.hydro.com (Terje Mathisen)
>I need the source code to (in TP and/or Assembly) setup a processor
>independant delay. The one I have is way faster on a 486 than on a 386.
>I need something that tests the machines speed when a unit is initialized
>and saves a number to a variable and then a delay procedure that uses
>that number.
Well, the Delay() procedure in the Crt unit is designed to do exactly this,
but if you cannot use Crt, try this replacement which I wrote almost
10 years ago, and later converted to a Unit.
}
{$R-,S-}
Unit Delays;
INTERFACE
CONST loop_count : WORD = 250;
PROCEDURE Delay(ms : WORD);
IMPLEMENTATION
PROCEDURE Delay(ms : Word);
BEGIN
Inline(
$8B/$76/LOOP_COUNT {d0: mov cx,[>loop_count]}
/$E2/$FE {d1: loop d1}
/$4E { dec si}
/$75/$F7 { jnz d0}
); {d2:}
END;
BEGIN
InLine(
$B8/$40/$00 { mov ax,$40}
/$8E/$C0 { mov es,ax}
/$BB/$6C/$00 { mov bx,$6C}
/$26/$8B/$37 {d3: es: mov si,[bx]}
/$31/$FF { xor di,di}
/$26/$3B/$37 {d4: es: cmp si,[bx]}
/$74/$FB { je d4}
/$26/$8B/$37 { es: mov si,[bx]}
/$8B/$0E/>LOOP_COUNT {d5: mov cx,[>loop_count]}
/$E2/$FE {d6: loop d6}
/$47 { inc di}
/$26/$3B/$37 { es: cmp si,[bx]}
/$74/$F4 { je d5}
/$A1/>LOOP_COUNT { mov ax,[>loop_count]}
/$F7/$E7 { mul di}
/$B9/$37/$00 { mov cx,55}
/$F7/$F1 { div cx}
/$A3/>LOOP_COUNT { mov [>loop_count],ax}
/$81/$FF/$1E/$00 { cmp di,30}
/$72/$D4 { jb d3}
);
END.