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;* VeriPrint - Checks if LPT1 (PRN) is available.
;*
;* Shows:   BIOS Interrupt - 17h (Parallel Port Printer Driver)
;*
;* Params:  None
;*
;* Return:  Short integer, 1 for yes or 0 for no
 
VeriPrint PROC
 
        mov     ah, 2                   ; Check printer status for
        sub     dx, dx                  ;   parallel printer (port 0)
        int     17h
        xchg    dx, ax                  ; Put 0 (for error) in AX
        test    dh, 00101001b           ; Are any error bits on?
        jne     exit                    ; Yes?  Leave 0
        test    dh, 10010000b           ; Are both operation bits on?
        jz      exit                    ; No?  Leave 0
        inc     ax                      ; Yes?  Return 1
exit:   ret
 
VeriPrint ENDP
                                    -♦-