-
Notifications
You must be signed in to change notification settings - Fork 1
/
Copy pathscroll.asm
285 lines (171 loc) · 7.71 KB
/
scroll.asm
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
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
; extra MACRO files need to go here
include "myMacros.inc"
.assume adl=1 ; ez80 ADL memory mode
.org $40000 ; load code here
jp start_here ; jump to start of code
.align 64 ; MOS header
.db "MOS",0,1
start_here:
push af ; store all the registers
push bc
push de
push ix
push iy
; ------------------
; This is our actual code
; prepare the screen
SET_MODE 8 ; mode 8 is 640x480 pixels, 64 colours
; Sending a VDU byte stream
ld hl, VDUdata ; address of string to use
ld bc, endVDUdata - VDUdata ; length of string
rst.lil $18 ; Call the MOS API to send data to VDP
ld a, $08 ; code to send to MOS
rst.lil $08 ; get IX pointer to System Variables
; ------------------
LOOP_HERE: ; loop here until we hit ESC key
MOSCALL $1E ; load IX with keymap address
ld a, (ix + $0E)
bit 0, a ; index $0E, bit 0 is for ESC key in matrix
jp nz, EXIT_HERE ; if pressed, ESC key to exit
MOSCALL $1E ; load IX with keymap address
ld a, (ix + $03)
bit 1, a ; index $06 bit 0 is for 'left' key in matrix
call nz, scroll_left ; if pressed, setFrame1
MOSCALL $1E ; load IX with keymap address
ld a, (ix + $0F)
bit 1, a ; index $06 bit 0 is for 'left' key in matrix
call nz, scroll_right ; if pressed, setFrame1
MOSCALL $1E ; load IX with keymap address
ld a, (ix + $07)
bit 1, a ; index $06 bit 0 is for 'left' key in matrix
call nz, scroll_up ; if pressed, setFrame1
MOSCALL $1E ; load IX with keymap address
ld a, (ix + $05)
bit 1, a ; index $06 bit 0 is for 'left' key in matrix
call nz, scroll_down ; if pressed, setFrame1
jp LOOP_HERE
; ------------------
scroll_left:
ld a, 1
ld (scrollDirection), a
call doScroll
ret
scroll_right:
ld a, 0
ld (scrollDirection), a
call doScroll
ret
scroll_up:
ld a, 3
ld (scrollDirection), a
call doScroll
ret
scroll_down:
ld a, 2
ld (scrollDirection), a
call doScroll
ret
; ------------------
doScroll:
ld hl, scrollData ; address of string to use
ld bc, endScrollData - scrollData ; length of string
rst.lil $18 ; Call the MOS API to send data to VDP
ld a, 00010000b
call multiPurposeDelay
ret
; Scroll the screen
; VDU 23, 7, extent, direction, speed
scrollData:
.db 23, 7, 2 ; extent: 0 = text viewport, 1 = whole screen
; 2 = graphics viewport
scrollDirection: .db 0 ; direction: 0 right, 1 left, 2 down, 3 up
.db 1 ; speed = number of pixels
endScrollData:
; ------------------
; This is where we exit the program
EXIT_HERE:
CLS
pop iy ; Pop all registers back from the stack
pop ix
pop de
pop bc
pop af
ld hl,0 ; Load the MOS API return code (0) for no errors.
ret ; Return to MOS
; ------------------
; This is the data we send to VDP
VDUdata:
.db 23, 0, 192, 0 ; set to non-scaled graphics
.db 17, 128 +7 ; background text black
.db 12 ; cls
.db 24 ; set graphics viewport:-
.dw 40, 150, 270, 40 ; 24, left; bottom; right; top;
.db 17, 128 ; background text grey
.db 12 ; cls
; FOR A SINGLE PIXEL PLOT
.db 18, 0, bright_red ; set graphics colour: mode (0), colour
.db 25, 69 ; PLOT: mode (69 is a point in current colour),
.dw 200,80 ; X; Y;
; FOR A LINE
.db 18, 0, bright_magenta ; set graphics colour: mode (0), colour
.db 25, 69 ; PLOT: mode (69 is a point in current colour),
.dw 300, 60 ; X; Y;
.db 25, 13 ; PLOT: mode (13 is a line),
.dw 250,130 ; X; Y;
; FOR A RECTANGLE
.db 18, 0, green ; set graphics colour: mode (0), colour
.db 25, 69 ; PLOT: mode (69 is a point in current colour),
.dw 10,120 ; X; Y;
.db 25, 101 ; PLOT: mode (101 is a filled rectangle),
.dw 100,180 ; X; Y;
; FOR A CIRCLE
.db 18, 0, bright_yellow ; set graphics colour: mode (0), colour
.db 25, 68 ; PLOT: mode (69 is a MOVE TO but don't plot point),
.dw 180,140 ; X; Y;
.db 25, 149 ; PLOT: mode (149 is an outlined circle),
.dw 200,160 ; X; Y;
; FOR A FILLED TRIANGLE
.db 18, 0, blue ; set graphics colour: mode (0), colour
.db 25, 69 ; PLOT: mode (69 is a point in current colour),
.dw 10,10 ; X; Y;
.db 25, 69 ; PLOT: mode (69 is a point in current colour),
.dw 50, 100 ; X; Y;
.db 25, 85 ; PLOT: mode (85 is a filled triangle),
.dw 200,20 ; X; Y;
endVDUdata:
; ------------------
; colour data
bright_red: equ 9
green: equ 2
bright_yellow: equ 11
bright_magenta: equ 13
blue: equ 4
white: equ 7
black: equ 0
bright_white: equ 15
; ------------------
multiPurposeDelay:
push bc
ld b, a
MOSCALL $08 ; get IX pointer to sysvars
waitLoop:
ld a, (ix + 0) ; ix+0h is lowest byte of clock timer
; we check if bit set is same as last time we checked.
; bit 0 - don't use
; bit 1 - changes 64 times per second
; bit 2 - changes 32 times per second
; bit 3 - changes 16 times per second
; bit 4 - changes 8 times per second
; bit 5 - changes 4 times per second
; bit 6 - changes 2 times per second
; bit 7 - changes 1 times per second
and b
ld c,a
ld a, (oldTimeStamp)
cp c ; is A same as last value?
jr z, waitLoop ; loop here if it is
ld a, c
ld (oldTimeStamp), a ; set new value
pop bc
ret
oldTimeStamp: .db 00h