***************************************************************
*                                                             *
* A PASCAL/Z EXTERNAL ROUTINE TO DETERMINE WHICH DISK-DRIVE   *
* IS CURRENTLY LOGGED IN.THE CALLING PROGRAM MUST DECLARE     *
*                                                             *
*         VAR DRIVE:CHAR;                                     *
*                                                             *
*         PROCEDURE DRVLOG( VAR DRIVE : CHAR );EXTERNAL;      *
*                                                             *
***************************************************************

                 NAME DRVLOG
                 ENTRY DRVLOG

VBYTES EQU 02    # OF BYTES ON STACK
DRVPTR EQU 09    OFFSET TO (IX) FOR HI-BYTE OF ADDRESS OF "DRIVE"

DRVLOG: ENTR D,2,0
        MVI C,25              ASK CP/M FOR # OF
        CALL 5                LOGGED-IN DRIVE,
        ADI 41H               CONVERT TO ASCII,
        MOV H,DRVPTR(IX)      GET ADDRESS OF "DRIVE"
        MOV L,DRVPTR-1(IX)    INTO HL REGISTER,
        MOV M,A               STORE DRIVE# IN "DRIVE",
        EXIT D,VBYTES

        END DRVLOG