;This code is listed here for entertainment value only, it should 
;not be used for anything important.  Do not use this for a saleable product.  
;Feel free to pass this on to others in it's entirety. along with this message.
;No Guarantees implicit or otherwise are implied, your mileage may vary. 

        $RB(0)
        $RB(1)
$NOMOD51 INCLUDE(87C752.pdf)
$INCLUDE(common.inc)

        EXTRN        CODE(_MAIN)

PUBLIC CRH0

        USING 0
        USING 1
        USING 2
        USING 3

CLIBC SEGMENT CODE
        RSEG    CLIBC


                               ; RESET HANDLER
CRH0:
        MOV     SP,#LOW CSTACK ; INITIALIZE STACK POINTER
        MOV     PSW,#00        ; CLEAR PSW
        MOV     R0,#IBUFSTART  ; SET head of circular character input buffer.
        MOV     R1,#IBUFSTART  ; SET tail of circular character input buffer.

        SETB    RS0
        MOV     R0,#OBUFSTART ; SET head of circular character output buffer.
        MOV     R1,#OBUFSTART ; SET tail of circular character output buffer.
        CLR     RS0

        MOV     IE,#1          ; only set external interrupt 0 to enabled
        MOV     COL,#0         ; set lcd column to zero
        MOV     ROW,#0         ; set lcd row to zero


        MOV     I2CON,#0       ; I have no idea what I'm doing here.

        MOV     PWENA,#1       ; Set PWM output for LED status.
        MOV     PWMP,#128      ; Use a low frequency.
        MOV     PWCM,#128      ; Start out with a neutral color.

        SETB    KP_R1          ; Ensure all keypad rows are floating high
        SETB    KP_R2
        SETB    KP_R3
        SETB    KP_R4

        CLR     SWR            ; Don't screw up the common write between
                               ; other keypads

        MOV     ADCON,#(ENADC OR ADCS OR AADR1)
                               ; Enable A/D converter, and select input 2.

        MOV     P3,#LOW(NOT (EN OR EN2))        
                               ; set up P3 for lcd & keypad

        SETB    EA             ; Set interrupts to enabled.

        AJMP        _MAIN      ; Execute main loop

?STACK        SEGMENT        IDATA
        RSEG    ?STACK

CSTACK:
        DS      1              ; SYSTEM STACK

$EJECT
        END