cpuinfo.c

得到CPU的类型(C++源程序)

#include <stdio.h>
#include <stdlib.h>
#include <dos.h>

#define         _8088           0
#define         _NECV20         1
#define         _80188          2
#define         _80286          3
#define         _80386          4


char *CPUStrings[] =
                {
                   "8088/8086",
                   "NEC V20/V30",
                   "80188/80186",
                   "80286",
                   "80386"
                };


int CPUInfo( void )
{
    /* ---------------------------------------------------------------- */
    /* The following Code distinguishes between 286+ (and above) and    */
    /* the other chips since 286+ (and above) pushes SP prior to        */
    /* decrementing its value for a PUSH SP instruction...  The earlier */
    /* processors will decrement SP first...                            */
    /* ---------------------------------------------------------------- */
    __emit__(0x8B,0xDC);                        /* MOV    BX, SP        */
    __emit__(0x54);                             /* PUSH   SP            */
    __emit__(0x58);                             /* POP    AX            */
    __emit__(0x87,0xE3);                        /* XCHG   BX, SP        */
    if ( _AX == _BX )
    {
    /* ---------------------------------------------------------------- */
    /* The following Code distinguishes between a 286 and higher        */
    /* processors since the 286 sets bits 12-14 of the FLAGS to zero    */
    /* after a PUSHF...                                                 */
    /* ---------------------------------------------------------------- */
        __emit__(0xB8,0x00,0x70);               /* MOV    AX, 7000h     */
        __emit__(0x50);                         /* PUSH   AX            */
        __emit__(0x9D);                         /* POPF                 */
        __emit__(0x9C);                         /* PUSHF                */
        __emit__(0x58);                         /* POP    AX            */

        if ( ( _AX & 0x7000 )==0x0000 )
            return( _80286 );
        else
            return( _80386 );
    }

    /* ---------------------------------------------------------------- */
    /* The Following Code singles out the 80186 and 80188 since the Top */
    /* three bits in CL are excluded by a shift instruction on those    */
    /* processors... i.e. Only the lower 5 bits of CL is used.. Using   */
    /* the value of 33 in CL is guaranteed to clear the register with   */
    /* the lower processors..                                           */
    /* ---------------------------------------------------------------- */
    __emit__(0xB0, 0xFF);                       /* MOV    AL, 0FFh      */
    __emit__(0xB1, 0x21);                       /* MOV    CL, 21h       */
    __emit__(0xD2, 0xE8);                       /* SHR    AL, CL        */

    if ( _AL != 0x00 )
        return( _80188 );

    /* ---------------------------------------------------------------- */
    /* The NEC V20/V30 carry forth a string instruction with REP and    */
    /* segment override even when Interrupts are enabled (unlike the    */
    /* 8088/8086)...                                                    */
    /* ---------------------------------------------------------------- */
    enable();                                   /* Ensure int's enabled */
    __emit__(0x56);                             /* PUSH   SI            */
    __emit__(0xB9,0xFF,0xFF);                   /* MOV    CX, 0FFFFh    */
    __emit__(0xF3,0x26,0xAC);                   /* REP LODS BPTR ES:[SI]*/
    __emit__(0x5E);                             /* POP    SI            */
    if ( _CX == 0x00 )
        return( _NECV20 );
    return(  _8088 );
}






int main(void)
{
    printf("CPU Detection Routine\n");
    printf("--- --------- -------\n\n");
    printf("Current Processor is: %s\n\n", CPUStrings[ CPUInfo() ]);
    return( 0 );
}