-
Notifications
You must be signed in to change notification settings - Fork 1
/
odc2.a48
421 lines (335 loc) · 6.9 KB
/
odc2.a48
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
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
; Copyright (C) 1997-1999 by Soeren Gust, [email protected]
; Copyright (C) 2010 by Felipe Corrêa da Sanches, [email protected]
; Copyright (C) 2010 by Leandro Lameiro, [email protected]
; Copyright (C) 2010 by Niels van Dijkhuizen, [email protected]
; This program is free software; you can redistribute it and/or modify
; it under the terms of the GNU General Public License as published by
; the Free Software Foundation; either version 2 of the License, or
; (at your option) any later version.
;
; This program is distributed in the hope that it will be useful,
; but WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
; GNU General Public License for more details.
;
; You should have received a copy of the GNU General Public License
; along with this program; if not, write to the Free Software
; Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
cpu 8048
time_parameter equ 20h
yoffs equ 21h
snow_x0 equ 22h
N1 equ 00h
N2 equ 04h
N3 equ 08h
N4 equ 0ch
N5 equ 10h
N6 equ 14h
N7 equ 18h
N8 equ 1ch
N9 equ 20h
N10 equ 24h
N11 equ 12h
TONE equ 80h
NOISE equ 40h
PAUSE equ 20h
JUMPTO equ 10h
org 400h
include "bitfuncs.inc"
include "g7000.h"
jmp selectgame ; RESET
jmp irq ; interrupt
jmp timer ; timer
jmp vsyncirq ; VSYNC-interrupt
jmp start ; after selectgame
jmp mysoundirq ; sound-interrupt
timer retr ; we don't need timer
;calc_cos:
; input:
;A <-- alpha
; output:
;A --> 128 + 128*cos(alpha)
calc_sin
add a,#16*3 ; shift -90 degrees = +270 degrees (64 steps = 2pi radians = 360 degrees)
calc_cos
anl a, #03fh ;mask-in 6 lower bits (limit to range 0-63)
add a,#lo(cos_table)
movp a,@a
ret
cos_table
include "cos_table.inc"
rewired_str
db 7
db _R, _E, _W, _I, _R, _E, _D
_2010_str
db 4
db _2, _0, _1, _0
start
mov r0, #lo(snow_x0)
mov a, #0
mov @r0, a
inc r0
mov a, #80
mov @r0, a
inc r0
mov a, #30
mov @r0, a
inc r0
mov a, #60
mov @r0, a
mov a, #lo(rewired_tune)
mov a, #76h
call playsound
main_loop
call waitvsync
;increment time time_parameter:
mov r0,#time_parameter
inc @r0
mov r0, #lo(yoffs)
mov @r0, #0
mov r7,#lo(rewired_str)
call print_string_in_circles
call print_snowflakes
;-----------------
;routine to wait for the middle of the screen:
mov r0, #0c0h
here0
mov r1, #02h
here1
djnz r1, here1
djnz r0, here0
;-----------------
mov r0, #lo(yoffs)
mov @r0, #80
mov r7,#lo(_2010_str)
call print_string_in_circles
jmp main_loop
setup_snow_char
mov r5, #29h ; char "x"
;is it odd?
anl a, #04h
jz odd_time_parameter
inc r5 ; char "%"
odd_time_parameter
ret
print_snowflakes
mov r0,#time_parameter
mov a,@r0
mov r1,a; r1 = time_parameter
mov r0,#vdc_char8
mov r2,#4; four snowflakes
snowflake
mov a, r1
call setup_snow_char
mov a, r1
mov r4, a ; y=time_parameter
call calc_cos
anl a, #0fch
rr a
rr a
mov r3,a ; x = 30 + 32 + 32*cos(time_parameter*2*pi/64)
;store copy of R0
mov a, r0
mov r7, a
mov a, r2
dec a
add a, #lo(snow_x0)
mov r0, a
mov a,@r0
;add initial x-offset to the calculated x-offset
add a, r3
mov r3, a
;restore R0
mov a, r7
mov r0, a
mov r6, #col_chr_white
call printchar
mov a, r1
add a, #60
mov r1, a ; different time_parameter for each snowflake
djnz r2, snowflake
ret
;input:
; R7 <-- string address
;output:
; NONE
;alters:
; A (R0) R1 R2 (R3) (R4) R5 R6 R7
print_string_in_circles
;ret
; read time time_parameter into R1:
mov r0,#time_parameter
mov a,@r0
;speed/4:
anl a, #0fch
rr a
rr a
mov r1,a ; r1=time_parameter/4
call gfxoff
mov a, r7
movp a,@a
mov r2,a
inc r7
mov r0,#vdc_char0
loop
mov a,r7
movp a,@a
mov r5,a
inc r7
mov a, #lo(string_colors)
add a, r2
movp a,@a
mov r6, a
call calc_char_position
dec r1
dec r1
; dec r1
call printchar ; print it
djnz r2,loop ; do it again
call gfxon
ret
string_colors
db col_chr_green, col_chr_red, col_chr_white
db col_chr_green, col_chr_red, col_chr_white
db col_chr_green, col_chr_red, col_chr_white
;old-colorful pallete
; db col_chr_violet, col_chr_green, col_chr_red, col_chr_blue, col_chr_yellow, col_chr_cyan
; db col_chr_violet, col_chr_green, col_chr_red, col_chr_blue, col_chr_yellow, col_chr_cyan
;input:
; R1 <- alpha
;output:
; R3 -> x = 8 + 64 + 64*sin(alpha*2*pi/64)
; R4 -> y = yoffset + 8 + 64 + 64*cos(alpha*2*pi/64)
;alters:
; A, R3, R4
;
calc_char_position
;add y offset to char coordinates (double sprites hack)
; mov r4,r0
mov a, r0
mov r4, a
mov r0, #lo(yoffs)
mov a, @r0
mov r3, a
;mov r0, r4
mov a,r4
mov r0,a
mov a, r3
mov r4, a ; r4=yoffs
mov a,r1
add a,r1
add a,r1
call calc_cos
anl a, #0fch ;mask out lower bits
rr a; divide by 2
rr a; divide by 2
add a, #48 ; add an x offset
add a, r4; add the initial yoffset
mov r4,a ;y-coordinate for char
mov a,r1
add a,r1
call calc_sin
anl a, #0fch
rr a
rr a
add a, #48 ; 8 pixel away from the border
mov r3,a ;x-coordinate for char
ret
org 0700h
mysoundirq
; check if BIOS sound or custom sound
mov a,r4
add a,#08ah ; >= 076h
jc .custom
jmp soundirq ; BIOS tune
.custom ; custom sound handler, read sound opcodes from current page
mov a,r4
movp a,@a
mov r1,a ; command byte
inc r4
xrl a,#0fh
jz .op0f ; test for new opcode
mov a,r4
movp a,@a
mov r2,a ; time_parameter byte
jmp parsesnd ; let BIOS sound IRQ handle opcode
; opcode 0F: sound off, copy next 3 bytes into A7/8/9
.op0f mov r0,#vdc_soundctrl
clr a
movx @r0,a ; old sound off
mov r0,#vdc_sound0
mov r1,#3 ; number of bytes to copy
.loop mov a,r4
movp a,@a
movx @r0,a
inc r0
inc r4
djnz r1,.loop
jmp mysoundirq ; restart sound handler
chord macro note1,note2
db TONE|2, note1
db TONE|2, note2
db TONE|2, note1
db TONE|2, note2
db TONE|2, note1
db TONE|2, note2
endm
noise macro length
db NOISE|length, 0FFh
endm
org 776h
rewired_tune
db TONE|12,N1
db PAUSE|4
noise 3
db PAUSE|3
db TONE|10,N2
db PAUSE|8
noise 3
db PAUSE|9
db TONE|10,N2
db PAUSE|8
noise 3
db PAUSE|9
;----2
db TONE|12,N1
db PAUSE|4
noise 3
db PAUSE|3
db PAUSE|10
db TONE|10,N2
db PAUSE|8
noise 3
db PAUSE|9
db TONE|10,N4
db PAUSE|8
noise 3
db PAUSE|9
;----3
chord N6,N7
db PAUSE|4
noise 3
db PAUSE|3
db TONE|10,N2
db PAUSE|8
noise 3
db PAUSE|9
db TONE|10,N2
db PAUSE|8
noise 3
db PAUSE|9
;----4
chord N4,N5
db PAUSE|4
noise 3
db PAUSE|3
db TONE|10,N2
db PAUSE|8
noise 3
db PAUSE|9
db TONE|10,N2
db PAUSE|8
noise 3
db PAUSE|9
;----
db JUMPTO, lo(rewired_tune)