!to"menu.prg",cbm
;----------------------------------------------------------
; Dynamic Lightbar for 6502-Assembler
;
; [/] 04.April 2011 M. Sachse http://www.cbmhardware.de
;----------------------------------------------------------
firstline = $0a
lastline = $0b
s_lo = $fb
s_hi = $fc
linelenght = $fe
get = $ffe4
*=$0800
!by $00,$0c,$08,$0a,$00,$9e,$32,$30,$36,$34,$00,$00,$00,$00
*=$0810
; setup
lda #$04 ; ofs first line
sta s_hi
lda #$f0
sta s_lo
lda #$28 ; lenght of the line
sta linelenght
lda #$00 ; first line (+ofs)
sta firstline
lda #$0d ; last line (+ofs)
sta lastline
; build inverted highlighting at first line
;
ldy #$00
- lda (s_lo),y
ora #%10000000
sta (s_lo),y
iny
cpy linelenght
bne -
; move by keyboard
main:
jsr get
cmp #$20 ; spc-key
beq end
cmp #$11 ; cursor up
beq move_up
cmp #$91 ; cursor down
beq move_down
jmp main
end: rts
; move-routines
move_down:
lda menuline
cmp lastline
bne +
jmp main
+ inc menuline
clc
ldy #$00
- lda (s_lo),y
and #%01111111
sta (s_lo),y
iny
bcc +
inc s_hi
+ cpy linelenght
bne -
lda s_lo
clc
adc #$28
sta s_lo
bcc +
inc s_hi
+ clc
ldy #$00
- lda (s_lo),y
ora #%10000000
sta (s_lo),y
iny
bcc +
inc s_hi
+ cpy linelenght
bne -
jmp main
move_up:
lda menuline
cmp firstline
bne +
jmp main
+ dec menuline
clc
ldy #$00
- lda (s_lo),y
and #%01111111
sta (s_lo),y
iny
bcc +
inc s_hi
+ cpy linelenght
bne -
lda s_lo
sec
sbc #$28
sta s_lo
bcs +
dec s_hi
+ clc
ldy #$00
- lda (s_lo),y
ora #%10000000
sta (s_lo),y
iny
bcc +
inc s_hi
+ cpy linelenght
bne -
jmp main
menuline !by $00Letzte Änderung: 2019-01-04 09:53:50
