1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
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. "INIT" segment is nothing special on the
; Creativision, it is part of the "ROM" memory.
.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
|
