(Comp.sys.handhelds)
Item: 3287 by erikmb at etek.chalmers.se
Author: [Erik Bryntse]
  Subj: Another demo for S-CHIP (v 1.1)
  Date: Tue May 28 1991

A SAMPLE PROGRAM FOR S-CHIP v1.1
================================

When I added the extra scroll functions to v1.1, I couldn't resist writing
a car race. It lets you drive your car on a small forest road in high speed.
Use 1 and 2 to steer it. Below is the CHIPPER source for this demo and the
ASCed version.

; CAR RACE DEMO FOR SUPER-CHIP v 1.1
; (and no complaining about the lack of comments, please)
; V3, V4 = OLD CAR COORD
; V5, V6 = CAR COORDINATES
; V7 = ROAD POS

        DB      #00, #FF
        LD      V5, 60
        LD      V6, 45
        LD      V7, 60
        LD      V3, V5
        LD      V4, V6
        LD      I, CAR
        DRW     V3, V4, 0

MLOOP:  LD      I, CAR
        DRW     V3, V4, 0
        DB      #00, #C3
        DRW     V5, V6, 0
        SE      VF, 0
        JP      EXIT
        LD      V0, V7
        CALL    PUTROAD
        LD      V3, V5
        LD      V4, V6
        LD      V0, #7
        SKNP    V0
        CALL    LEFT
        LD      V0, #8
        SKNP    V0
        CALL    RIGHT
        RND     V0, 3
        SNE     V0, 0
        CALL    RR
        RND     V0, 3
        SNE     V0, 0
        CALL    RL
        JP      MLOOP

EXIT:   JP      EXIT            ; FINISHED!


RIGHT:  ADD     V5, 1
        SNE     V5, 110
        LD      V5, 109
        RET

LEFT:   LD      V0, 1
        SUB     V5, V0
        SNE     VF, 0
        LD      V5, 0
        RET

RR:     ADD     V7, 1
        SNE     V7, 90
        LD      V7, 89
        RET

RL:     LD      V0, 1
        SUB     V7, V0
        SNE     VF, 0
        LD      V7, 0
        RET     


; PLACE NEW ROAD PART AT COORDINATE V0, 0
; IN:   V0
; OUT:  -
; USES: I, V0, V1

PUTROAD:

        LD      V1, 0
        LD      I, SROAD
        DRW     V0, V1, 3
        ADD     V0, 25
        DRW     V0, V1, 3
        RET


SROAD:  DB $10100000, $01000000, $10100000

CAR:    DB $00110000, $00001100
        DB $00111111, $11111100
        DB $00110010, $01001100
        DB $00000010, $01000000
        DB $00000100, $00100000 
        DB $00000100, $00100000
        DB $00000100, $00100000
        DB $00000100, $00100000
        DB $11110100, $00101111
        DB $11110100, $00101111
        DB $11111101, $10111111
        DB $11110110, $01101111
        DB $11110110, $01101111 
        DB $00000110, $01100000
        DB $00111111, $11111100
        DB $01111111, $11111110