; void cputc (char c);
;
- .export _cputcxy, _cputc, cputdirect, putchar
- .export newline, plot
- .exportzp CURS_X, CURS_Y
- .import _gotoxy
- .import popa
- .import xsize, revers
+ .export _cputcxy, _cputc, cputdirect, putchar
+ .export newline, plot
+ .destructor setsyscursor
+
+ .import _gotoxy
+ .import popa
+ .import PLOT
+
+ .import ktmp: zp, crtc: zp, CURS_X: zp, CURS_Y: zp, RVS: zp
+ .import CharPtr: zp
+
+ .include "cbm610.inc"
- .include "cbm610.inc"
- .include "../cbm/cbm.inc"
_cputcxy:
- pha ; Save C
- jsr popa ; Get Y
- jsr _gotoxy ; Set cursor, drop x
- pla ; Restore C
+ pha ; Save C
+ jsr popa ; Get Y
+ jsr _gotoxy ; Set cursor, drop x
+ pla ; Restore C
; Plot a character - also used as internal function
-_cputc: cmp #$0A ; CR?
- bne L1
- lda #0
- sta CURS_X
- beq plot ; Recalculate pointers
+_cputc: cmp #$0A ; CR?
+ bne L1
+ lda #0
+ sta CURS_X
+ beq plot ; Recalculate pointers
-L1: cmp #$0D ; LF?
- beq newline ; Recalculate pointers
+L1: cmp #$0D ; LF?
+ beq newline ; Recalculate pointers
; Printable char of some sort
- cmp #' '
- bcc cputdirect ; Other control char
- tay
- bmi L10
- cmp #$60
- bcc L2
- and #$DF
- bne cputdirect ; Branch always
-L2: and #$3F
+ cmp #' '
+ bcc cputdirect ; Other control char
+ tay
+ bmi L10
+ cmp #$60
+ bcc L2
+ and #$DF
+ bne cputdirect ; Branch always
+L2: and #$3F
cputdirect:
- jsr putchar ; Write the character to the screen
+ jsr putchar ; Write the character to the screen
; Advance cursor position
advance:
iny
- cpy xsize
+ cpy #XSIZE
bne L3
jsr newline ; new line
ldy #0 ; + cr
rts
newline:
- clc
- lda xsize
- adc CharPtr
- sta CharPtr
- bcc L4
- inc CharPtr+1
-L4: inc CURS_Y
- rts
+ clc
+ lda #XSIZE
+ adc CharPtr
+ sta CharPtr
+ bcc L4
+ inc CharPtr+1
+L4: inc CURS_Y
+ rts
; Handle character if high bit set
-L10: and #$7F
- cmp #$7E ; PI?
- bne L11
- lda #$5E ; Load screen code for PI
- bne cputdirect
-L11: ora #$40
- bne cputdirect ; Branch always
-
-; Set cursor position, calculate RAM pointers
-
-plot: ldy CURS_X
- ldx CURS_Y
- clc
- jmp PLOT
+L10: and #$7F
+ cmp #$7E ; PI?
+ bne L11
+ lda #$5E ; Load screen code for PI
+ bne cputdirect
+L11: ora #$40
+ bne cputdirect ; Branch always
; Write one character to the screen without doing anything else, return X
; position in Y
putchar:
- ldx IndReg
- ldy #$0F
- sty IndReg
- ora revers ; Set revers bit
- ldy CURS_X
- sta (CharPtr),y ; Set char
- stx IndReg
- rts
+ ldx IndReg
+ ldy #$0F
+ sty IndReg
+ ora RVS ; Set revers bit
+ ldy CURS_X
+ sta (CharPtr),y ; Set char
+ stx IndReg
+ rts
+
+; Set cursor position, calculate RAM pointers
+
+plot: ldx CURS_Y
+ lda LineLSBTab,x
+ sta CharPtr
+ lda LineMSBTab,x
+ sta CharPtr+1
+
+ lda IndReg
+ pha
+ lda #$0F
+ sta IndReg
+
+ ldy #$00
+ clc
+ sei
+ sta (crtc),y
+ lda CharPtr
+ adc CURS_X
+ iny
+ sta (crtc),y
+ dey
+ lda #$0E
+ sta (crtc),y
+ iny
+ lda (crtc),y
+ and #$F8
+ sta ktmp
+ lda CharPtr+1
+ adc #$00
+ and #$07
+ ora ktmp
+ sta (crtc),y
+ cli
+
+ pla
+ sta IndReg
+ rts
+
+; -------------------------------------------------------------------------
+; Cleanup routine that sets the kernal cursor position to ours
+
+.segment "PAGE2"
+
+setsyscursor:
+ ldy CURS_X
+ ldx CURS_Y
+ clc
+ jmp PLOT ; Set the new cursor
+
+; -------------------------------------------------------------------------
+; Low bytes of the start address of the screen lines
+
+.rodata
+
+LineLSBTab:
+ .byte $00,$50,$A0,$F0,$40,$90,$E0,$30
+ .byte $80,$D0,$20,$70,$C0,$10,$60,$B0
+ .byte $00,$50,$A0,$F0,$40,$90,$E0,$30
+ .byte $80
+; -------------------------------------------------------------------------
+; High bytes of the start address of the screen lines
+LineMSBTab:
+ .byte $D0,$D0,$D0,$D0,$D1,$D1,$D1,$D2
+ .byte $D2,$D2,$D3,$D3,$D3,$D4,$D4,$D4
+ .byte $D5,$D5,$D5,$D5,$D6,$D6,$D6,$D7
+ .byte $D7
projects / cc65 / blobdiff