Contributor: SWAG SUPPORT TEAM
{
Here is the code I use, adapted from the Intel Pentium Processor User's
Manual, Chapter 5. It sets the Test8086 global variable, making the values
of Test8086:
0 = 8086
1 = 80186/80286
2 =わ 80386
3 =わ 80386 (new)
4 = 80486 (new)
5 = Pentium (new)
6 = ??
Note that for Pentium and higher CPUs, the new CPUID instruction is used to
retrieve the processor family number. This code should work on post-Pentium
(80686-class) CPUs and Pentium compatibles, and could return numbers> 5.
}
program CPUTest;
{$IFDEF WINDOWS}
uses wincrt;
{$ELSE}
uses crt;
{$ENDIF}
begin
if (Test8086 = 2) then { RTL check stops at 2 = 386}
asm
inc Test8086 { 3 = 386, for consistency }
{ Do we have a 386 or a 486? }
{ Does pushf/popf preserve the Alignment Check bit? (386=no, 486=yes) }
mov bx, sp { save current stack pointer }
and sp, not 3 { align stack to avoid AC fault }
db 66ドル; pushf
db 66ドル; pop ax
db 66ドル; mov cx, ax
db 66,ドル 35ドル; dd 40000ドル { xor AC bit in EFLAGS }
db 66ドル; push ax
db 66ドル; popf
db 66ドル; pushf
db 66ドル; pop ax
db 66ドル; xor ax, cx { Is AC bit toggled? }
je @@1 { if not, we have a 386 }
and sp, not 3 { align stack to avoid AC fault }
db 66ドル; push cx
db 66ドル; popf { restore original AC bit }
mov sp, bx { restore original stack pointer }
mov Test8086, 4 { we know we have at least a 486 }
{ Do we have a 486 or a Pentium? }
{ Does pushf/popf preserve the CPUID bit? (486=no, P5=yes) }
db 66ドル; mov ax, cx { get original EFLAGS}
db 66,ドル 35ドル; dd 200000ドル { XOR id bit in flags}
db 66ドル; push ax
db 66ドル; popf
db 66ドル; pushf
db 66ドル; pop ax
db 66ドル; xor ax, cx { Is CPUID bit toggled? }
je @@1 { if not, we have a 486 }
db 66ドル; xor ax, ax
db $f,$a2 { CPUID, AX = 0 (get CPUID caps) }
db 66ドル; cmp ax, 1
jl @@1 { if < 1, then exit }
db 66ドル; xor ax, ax
db 66ドル; inc ax
db $f,$a2 { CPUID, AX = 1 (get CPU info) }
and ax, $f00 { mask out all but family id }
shr ax, 8
mov Test8086, al { Pentium family = 5 }
@@1:
end;
writeln('Test8086: ',Test8086);
end.