這個都是過去DOS時代的匯編源碼，雖然已經過去了，但是對於學習匯編還是有幫助的，匯編語言只是程序員一門基礎語言，大多人掌握即可，不一定要深入研究.......
; calling convention:
;
; int chips( void );
;
; returns:
;
; tucked away neatly in your AX....
;
; you get back 8x if an 8088/8086
; 18x if an 80186/80188
; 28x if an 80286
; 38x if an 80386
; 20x for a NEC V20/V30
; AND
; xx0 if NO NDP is found
; xx1 if an 8087
; xx2 if an 80287
; xx3 for an 80387
;
; OR.....
;
; >>> A return of 280 means you got an 80286 machine with no NDP, <<<
; >>> 383 means you have an 80386/80387 rig to work with, and a <<<
; >>> return of 81 sez that you have 8088/8086 CPU with an 8087. <<<
; >>> A 200 tells you that you got an NEC V20/V30 without an NDP. <<<
; >>> ETC., Etc., etc. <<<
;
; NOTE:
;
; There are lotsa ways of handling the way this function returns
; it's data. For my purposes, I have elected this one because
; it requires only int arithmetic on the caller's end to extract
; all the info I need from the return value. I think that I'm
; well enough 'commented' in the following code so that you will
; be able to tinker and Putz until you find the best return tech-
; nique for Ur purposes without having to reinvent the wheel.
;
; >>>> Please see TEST.C, enclosed in this .ARC. <<<<
;
; REFERENCES:
;
; _chips is made up of two PROC's, cpu_type and ndp_type.
;
; cpu_type is based on uncopyrighted, published logic by
; Clif (that's the way he spells it) Purkiser of Intel -
; Santa Clara.
;
; ndp_type is adopted from Ted Forgeron's article in PC
; Tech Journal, Aug '87 p43.
;
; In the event of subsequent republication of this function,
; please carry forward reference to these two gentlemen as
; original authors.
;
; Copr. 1987 Pat Shea - Psi! (that Copr. is on there cuz my
; lawyer sez I should, but feel
; free to hack away!!! pats.)
;
; Update: 1/1/88 - changed this code slightly so that it is
; compilable using MASM 5.0, and the test.c
; file using MSC 5.0. <Albert Stein>
.MODEL SMALL
.CODE
PUBLIC _chips
_chips PROC
control dw 0 ; control word needed for the NDP test
push BP ; save where Ur at
mov BP,SP ; going in.....
push DI
push SI
push CX ; not really needed for MSC but kinda
; nice to do cuz someone else might
; want to use the function and we do
; use CX later on
call cpu_type ; find out what kinda CPU you got and
; and save it in DX for future reference
call ndp_type ; check for math coprocessor (NDP) type
; and hold that result in AX
add AX,DX ; add the two results together and hold
; 'em in AX for Ur return to the caller
pop CX ; put things back the way that you
pop SI ; found 'em when you started this
pop DI ; little drill off.....
pop BP
; AND
ret ; go back to where you came from....
; ( ===> the calling program )
; with Ur results sittin' in AX !!
_chips endp
cpu_type PROC
pushf ; pump Ur flags register onto the stack
xor DX,DX ; blow out Ur DX and AX to start off
xor AX,AX ; with a clean slate
push AX ; put AX on the stack
popf ; bring it back in Ur flags
pushf ; try to set bits 12 thru 15 to a zero
pop AX ; get back Ur flags word in AX
and AX, 0f000h ; if bits 12 thru 15 are set then you got
cmp AX, 0f000h ; an Intel 8018x or a 808x or maybe even
jz dig ; a NEC V20/V30 ??? - gotta look more...
; OTHERWISE....
; Here's the BIG one.... 'tells the difference between an 80286 and
; an 80386 !!
mov AX, 07000h ; try to set FLAG bits 12 thru 14
; - NT, IOPL
push AX ; put it onto the stack
popf ; and try to pump 07000H into Ur flags
pushf ; push Ur flags, again
pop AX ; and bring back AX for a compare
and AX,07000h ; if Ur bits 12 thru 14 are set
jnz got386 ; then Ur workin' with an 80386
mov DX, 0280 ; save 280 in DX cuz it's an 80286
jmp SHORT CPUbye ; and bail out
got386: mov DX, 0380 ; save 380 in DX cuz it's an Intel 80386
jmp SHORT CPUbye ; and bail out
; here's we try to figger out whether it's an 80188/80186, an 8088/8086
; or an NEC V20/V30 - 'couple of slick tricks from Clif Purkiser.....
dig: mov AX, 0ffffh ; load up AX
mov CL, 33 ; HERE's the FIRST TRICK.... this will
; shift everything 33 times if it's
; 8088/8086, or once for a 80188/80186!
shl AX, CL ; on a shift of 33, all bits get zeroed
jz digmor ; out so if anything is left ON it's
; gotta be an 80188/80186
mov DX,0180 ; save 180 in DX cuz it's an 80188/80186
jmp SHORT CPUbye ; and bail out
digmor: xor AL,AL ; clean out AL to set ZF
mov AL,40h ; ANOTHER TRICK.... mul on an NEC duz NOT
mul AL ; effect the zero flag BUT on an Intel
jz gotNEC ; 8088/8086, the zero flag gets thrown
mov DX,0080 ; 80 into DX cuz it's an Intel 8088/8086
jmp SHORT CPUbye ; and bail out
gotNEC: mov DX,0200 ; it's an NEC V20/V30 so save 200 in DX
CPUbye: popf ; putchur flags back to where they were
ret ; and go back to where you came from
; (i.e., ===> _chips) with the CPU type
; tucked away in DX for future reference
cpu_type endp
; Check for an NDP.
;
; >>>>NOTE: If you are using an MASM version < 5.0, don't forget to
; use the /R option or you will bomb cuz of the coprocessor instruc-
; tions. /R is not needed for version 5.0.<<<<<<<<<<<<<<<<<<<<<<<<<
ndp_type PROC
do_we: fninit ; try to initialize the NDP
mov byte ptr control+1,0 ; clear memory byte
fnstcw control ; put control word in memory
mov AH,byte ptr control+1 ; iff AH is 03h, you got
cmp AH,03h ; an NDP on board !!
je chk_87 ; found somethin', keep goin'
xor AX,AX ; clean out AX to show a zero
jmp SHORT NDPbye ; return (i.e., no NDP)
; 'got an 8087 ??
chk_87: and control,NOT 0080h ; turn ON interrupts (IEM = 0)
fldcw control ; load control word
fdisi ; turn OFF interrupts (IEM = 1)
fstcw control ; store control word
test control,0080h ; iff IEM=1, 8087
jz chk287 ; 'guess not! March on....
mov AX,0001 ; set up for a 1 return to
jmp SHORT NDPbye ; show an 8087 is on board
; if not.... would you believe an 80287 maybe ??
chk287: finit ; set default infinity mode
fld1 ; make infinity
fldz ; by dividing
fdiv ; 1 by zero !!
fld st ; now make a
fchs ; negative infinity
fcompp ; compare Ur two infinities
fstsw control ; iff, for 8087 or 80287
fwait ; sit tight 'til status word is put away
mov AX,control ; getchur control word
sahf ; putchur AH into flags
jnz got387 ; NO GOOD.... march on !!
mov AX,0002 ; gotta be a 80287 cuz we already tested
jmp SHORT NDPbye ; for an 8087
; We KNOW that there is an NDP on board otherwise we would have bailed
; out after 'do_we'. It isn't an 8087 or an 80287 or we wouldn't have
; gotten this far. It's gotta be an 80387 !!
got387: mov AX,0003 ; call it an 80387 and return 3
NDPbye: ret ; and go back where you came from
; (i.e., ===> _chips) carrying the NDP
; type in Ur AX register
ndp_type endp
_text ends
end
