You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('') and can be up to 35 characters long.
208 lines
8.7 KiB
NASM
208 lines
8.7 KiB
NASM
; 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.


;


.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 