Initial Creativision Import

2013-12-05 11:40:44 +00:00
parent b5ed9a1eff
commit 11be575b6d
23 changed files with 956 additions and 0 deletions
--- a/libsrc/creativision/cputc.s
+++ b/libsrc/creativision/cputc.s
@@ -0,0 +1,125 @@
+;
+; Written by Groepaz/Hitmen <groepaz@gmx.net>
+; Cleanup by Ullrich von Bassewitz <uz@cc65.org>
+;
+; void cputcxy (unsigned char x, unsigned char y, char c);
+; void cputc (char c);
+;
+
+        .export         _cputcxy, _cputc, cputdirect, putchar
+        .export         newline
+        .constructor    initconio
+        .import         popa, _gotoxy
+        .import         setcursor
+
+        .importzp       tmp3,tmp4
+
+        .include        "creativision.inc"
+        .include        "boxchars.inc"
+
+;-----------------------------------------------------------------------------
+
+.code
+
+_cputcxy:
+        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     #$0d            ; CR?
+        bne     L1
+        lda     #0
+        sta     CURSOR_X
+        beq     plot            ; Recalculate pointers
+
+L1:     cmp     #$0a            ; LF?
+        beq     newline         ; Recalculate pointers
+
+; Printable char of some sort
+
+cputdirect:
+        jsr     putchar         ; Write the character to the screen
+
+; Advance cursor position
+
+advance:
+        ldy     CURSOR_X
+        iny
+        cpy     #SCREEN_COLS
+        bne     L3
+        inc     CURSOR_Y          ; new line
+        ldy     #0              ; + cr
+L3:     sty     CURSOR_X
+        jmp     plot
+
+newline:
+        inc     CURSOR_Y
+
+; Set cursor position, calculate RAM pointers
+
+plot:   ldy     CURSOR_X
+        ldx     CURSOR_Y
+        jmp     setcursor       ; Set the new cursor
+
+
+; Write one character to the screen without doing anything else, return X
+; position in Y
+
+putchar:
+        cmp     #$5B
+        bcc     IS_UPPER
+
+        clc
+        sbc     #$1F
+
+IS_UPPER:
+        cmp     #$20
+        bcc     BAD_CHAR
+
+        pha
+        lda     SCREEN_PTR
+        sei
+        sta             VDP_CONTROL_W
+        lda     SCREEN_PTR+1
+        ora             #$40
+        sta             VDP_CONTROL_W
+        pla
+        clc
+        adc             #160
+        sta             VDP_DATA_W
+        cli
+
+BAD_CHAR:
+        jmp     plot
+        
+;-----------------------------------------------------------------------------
+; Initialize the conio subsystem. Code goes into the INIT segment, which may
+; be reused after startup.
+
+.segment        "INIT"
+
+initconio:
+    lda #$0
+    sta SCREEN_PTR
+    lda #$10
+    sta SCREEN_PTR+1
+
+    ; Copy box characters to slot
+    sei
+    lda #08
+    sta VDP_CONTROL_W
+    lda #$46
+    sta VDP_CONTROL_W
+    ldx #0
+LL:
+    lda boxchars,x
+    sta VDP_DATA_W
+    inx
+    cpx #48
+    bne LL      
+
+    cli
+    jmp plot