Product specifications

DOT9: INC H ;Increment X coord held in register H
;by 1 to move onto bottom right hand
;quadrant centre of sprite
PUSH HL ;Save HL register pair
CALL DOTSUB ;(See description in section DOT1)
POP HL ;Retrieve saved HL register pair
LD (SPRP9),A ;Store character value under bottom
;right hand quadrant centre of sprite
;in SPRP9
LD (CENLBR),A ;Store character value under bottom
;right hand quadrant centre of sprite
;in SPRP9
;
DOT10: DEC H ;Decrement X coord held in register H
LD A,L ;by 1 and increment Y coord held in
ADD A,7 ;register L by 7 to move onto bottom
LD L,A ;middle of sprite
PUSH HL ;Save HL register pair
CALL DOTSUB ;(See description in section DOT1)
POP HL ;Retrieve saved Hl register pair
LD (SPRP11),A :Store character value under bottom
;middle of sprite in SPRP11
;
DOT11: LD A,H ;Decrement X coord held in register H
SUB 7 ;by 7 to move onto bottom left hand
LD H,A ;corner of sprite
PUSH HL ;Save HL register pair
CALL DOTSUB ;(See description in section DOT1)
POP HL ;Retrieve saved HL register pair)
LD (SPRP10),A :Store character value under bottom
;left hand corner of sprite in SPRP10
;
DOT12: LD A,H ;Increment X coord held in register H
ADD A,15 ;by 15 to move onto bottom right hand
LD H,A ;corner of sprite
PUSH HL ;Save HL register pair
CALL DOTSUB ;(See description in section DOT1)
POP HL ;Retrieve saved HL register pair
LD (SPRP12),A ;Store character value under bottom
;right hand corner of sprite in SPRP12
RET ;Return to calling routine
;
;DOTSUB-DERIVES SCREEN LOCATION OF A POINT WITHIN A SPRITE
PATTERN AND BYTE HELD WITHIN THE SCREEN ADDRESS
;
; X COORD IN H, Y COORD IN L ON ENTRY
;
; LOCATION ON SCREEN IN DE
; BYTE IN A
; ON EXIT
;
; AF, BC, DE, HL REGISTER PAIRS AFFECTED ON EXIT