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testpico: check more settable bits
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1###############################################################################
2#
3# Copyright (c) 2009,2011 GraÅžvydas Ignotas
4# All rights reserved.
5#
6# Redistribution and use in source and binary forms, with or without
7# modification, are permitted provided that the following conditions are met:
8# * Redistributions of source code must retain the above copyright
9# notice, this list of conditions and the following disclaimer.
10# * Redistributions in binary form must reproduce the above copyright
11# notice, this list of conditions and the following disclaimer in the
12# documentation and/or other materials provided with the distribution.
13# * Neither the name of the organization nor the
14# names of its contributors may be used to endorse or promote products
15# derived from this software without specific prior written permission.
16#
17# THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND ANY
18# EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20# DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY
21# DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
26# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27#
28# Assemble with gas
29# --register-prefix-optional --bitwise-or
30#
31
32.equ USE_VINT, 0
33.equ COPY_TO_EXP, 1
34.equ RELOCATE_TO_RAM, 1
35
36.text
37.globl main
38.globl INT
39.globl VBL
40.globl return_to_main
41
42##################################################
43# #
44# Register and bitmask definitions #
45# #
46##################################################
47
48.equ GFXDATA, 0xc00000
49.equ GFXCNTL, 0xc00004
50
51.equ VDP0_E_HBI, 0x10
52.equ VDP0_E_DISPLAY, 0x02
53.equ VDP0_PLTT_FULL, 0x04
54
55.equ VDP1_SMS_MODE, 0x80
56.equ VDP1_E_DISPLAY, 0x40
57.equ VDP1_E_VBI, 0x20
58.equ VDP1_E_DMA, 0x10
59.equ VDP1_NTSC, 0x00
60.equ VDP1_PAL, 0x08
61.equ VDP1_MODE5, 0x04
62
63.equ VDP12_STE, 0x08
64.equ VDP12_SCREEN_V224, 0x00
65.equ VDP12_SCREEN_V448, 0x04
66.equ VDP12_PROGRESSIVE, 0x00
67.equ VDP12_INTERLACED, 0x02
68.equ VDP12_SCREEN_H256, 0x00
69.equ VDP12_SCREEN_H320, 0x81
70
71.equ VDP16_MAP_V32, 0x00
72.equ VDP16_MAP_V64, 0x10
73.equ VDP16_MAP_V128, 0x30
74.equ VDP16_MAP_H32, 0x00
75.equ VDP16_MAP_H64, 0x01
76.equ VDP16_MAP_H128, 0x03
77
78.equ MMODE_MAIN, 0
79.equ MMODE_VAL_INPUT, 1
80.equ MMODE_EDIT_VAL, 2
81.equ MMODE_GOTO, 3
82.equ MMODE_START_MENU, 4
83.equ MMODE_GOTO_PREDEF, 5
84.equ MMODE_JMP_ADDR, 6
85.equ MMODE_PC, 7
86
87.equ predef_addr_cnt, ((predef_addrs_end-predef_addrs)/4)
88
89##################################################
90# #
91# MACROS #
92# #
93##################################################
94
95
96# Write val to VDP register reg
97.macro write_vdp_r_dst reg val dst
98 move.w #((\reg << 8) + 0x8000 + \val),\dst
99.endm
100
101# Write val to VDP register reg, vdp addr in a3
102.macro write_vdp_reg reg val
103 write_vdp_r_dst \reg, \val, (a3)
104.endm
105
106# Set up address in VDP, control port in dst
107.macro VRAM_ADDR adr dst
108 move.l #(0x40000000 | ((\adr & 0x3fff) << 16) | (\adr >> 14)),\dst
109.endm
110
111.macro VSRAM_ADDR adr dst
112 move.l #(0x40000010 | ((\adr & 0x3fff) << 16) | (\adr >> 14)),\dst
113.endm
114
115
116# make VDP word from address adr and store in d0
117.macro XRAM_ADDR_var adr
118 move.l \adr,d0
119 lsl.l #8,d0
120 lsl.l #8,d0
121 rol.l #2,d0
122 lsl.b #2,d0
123 lsr.l #2,d0
124.endm
125
126
127.macro VRAM_ADDR_var adr
128 XRAM_ADDR_var \adr
129 or.l #0x40000000,d0
130.endm
131
132
133.macro CRAM_ADDR_var adr
134 XRAM_ADDR_var \adr
135 or.l #0xc0000000,d0
136.endm
137
138
139# convert tile coords in d0, d1 to nametable addr to a0
140.macro XY2NT
141 lsl.w #6,d1
142 add.w d1,d0
143 lsl.w #1,d0
144 movea.l #0xe000,a0
145 add.w d0,a0
146.endm
147
148# check if some d-pad button (and modifier) is pressed
149.macro do_dpad bit op val
150 btst.l #\bit,d0
151 beq 0f
152 \op \val,a6
153 bra dpad_end
1540:
155.endm
156
157# convert a6 to normal addr
158# destroys d0
159.macro mk_a6_addr reg
160 move.l a6,\reg
161 moveq.l #0,d0
162 move.b \reg,d0
163 lsr.l #8,\reg
164 add.l d0,\reg
165.endm
166
167.macro change_mode mode_new mode_back
168 and.w #0xc0ff,d7
169 or.w #(\mode_back<<11)|(\mode_new<<8),d7
170.endm
171
172# destroys a0,d0-d2
173.macro menu_text str x y pal
174 lea (\str,pc),a0
175 move.l #\x,d0
176 move.l #\y,d1
177 move.l #0x8000|(\pal<<13),d2
178 jsr print
179.endm
180
181#################################################
182# #
183# DATA #
184# #
185#################################################
186
187colors:
188 dc.w 0x0000,0x0eee,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000
189 dc.w 0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000
190 dc.w 0x0000,0x02e2,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000
191 dc.w 0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000
192 dc.w 0x0000,0x0e44,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000
193 dc.w 0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000
194 dc.w 0x0000,0x044e,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000
195 dc.w 0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000
196colors_end:
197
198
199sprite_data:
200 /* Y size link attr X */
201 dc.w 0; dc.b 0x05; dc.b 0; dc.w 0x6002; dc.w 0
202sprite_data_end:
203
204predef_addrs:
205 dc.l 0x000000, 0x200000, 0x400000, 0xa00000, 0xa10000
206 dc.l 0xa11100, 0xa12000, 0xa13000, 0xa14000, 0xa15100
207 dc.l 0xc00000
208predef_addrs_end:
209
210safe_addrs:
211 dc.l 0x000000, 0x7fffff
212 dc.l 0xe00000, 0xffffff
213 dc.l 0xa00000, 0xa100ff
214 dc.l 0xa11000, 0xa113ff
215 dc.l 0xa12000, 0xa120ff
216 dc.l 0xa13000, 0xa130ff
217safe_addrs_end:
218 dc.l 0xa15100, 0xa1513f
219safe_addrs_end_32x:
220 dc.l 0xa15180, 0xa153ff
221safe_addrs_end_32x_vdp:
222
223sizeof_bin:
224 dc.l _edata
225
226txt_edit:
227 .ascii "- edit -\0"
228txt_a_confirm:
229 .ascii "A-confirm\0"
230txt_about:
231 .ascii "hexed r2\0"
232txt_goto:
233 .ascii "Go to address\0"
234txt_goto_predef:
235 .ascii "Go to (predef)\0"
236txt_jmp_addr:
237 .ascii "Jump to address\0"
238txt_dump:
239 .ascii "PC Transfer\0"
240txt_dtack:
241 .ascii "DTACK safety\0"
242txt_transfer_ready:
243 .ascii "Transfer Ready\0"
244txt_working:
245 .ascii "PC mode \0"
246txt_dtack_err:
247 .ascii "DTACK err?\0"
248txt_exc:
249 .ascii "Exception \0"
250
251##################################################
252# #
253# MAIN PROGRAM #
254# #
255##################################################
256
257# global regs:
258# a6 = page_start[31:8]|cursor_offs[7:0]
259# d7 = old_inputs[31:16]|edit_bytes[15:14]|g_mode_old[13:11]|g_mode[10:8]|irq_cnt[7:0]
260# d6 = edit_word_save[31:15]|edit_done[7]|no_dtack_detect[4]|autorep_cnt[3:0]
261# d5 = main: tmp
262# edit: edit_word[31:8]|edit_pos[4:2]|byte_cnt[1:0]
263# menu: sel
264
265.align 2
266
267main:
268 /* make sure io port 2 is doing inputs */
269 move.b #0,(0xa1000b).l
270 /* make sure irqs are masked */
271 move.w #0x2700,sr
272 /* take care of TMSS */
273 move.b (0xa10000).l,d0
274 andi.b #0x0f,d0
275 beq no_tmss
276 move.l #0x53454741,(0xa14000).l
277 /* want cart, not OS rom if cart pops in */
278 move.w #1,(0xa14100).l
279 /* touch VDP after TMSS setup? */
280 tst.w (0xc00004).l
281no_tmss:
282
283 /* want to do early PC transfer (with RAM/VRAM intact and such)?
284 * also give time PC to see start condition */
285 move.l #0x2000,d0
2860: dbra d0,0b
287
288 move.l #0xa10005,a0
289 btst.b #5,(a0)
290 bne no_early_transfer
291move.b #1,(0)
292 move.b #0x40,(0xa1000b).l /* port 2 ctrl */
293 move.b #0x00,(a0) /* port 2 data - start with TH low */
294 move.l #0x2000,d0
2950:
296 btst.b #4,(a0)
297 beq do_early_transfer
298 dbra d0,0b
299
300move.b #2,(0)
301 move.b #0,(0xa1000b).l
302 bra no_early_transfer /* timeout */
303
304do_early_transfer:
305move.b #9,(0)
306 bsr do_transfer
307
308no_early_transfer:
309
310.if COPY_TO_EXP
311 /* copy to expansion device if magic number is set */
312 move.l #0x400000,a1
313 cmp.w #0x1234,(a1)
314 bne 0f
315
316 move.l #0,a0
317 move.l (sizeof_bin,pc),d0
318 lsr.l #3,d0
3191:
320 move.l (a0)+,(a1)+
321 move.l (a0)+,(a1)+
322 dbra d0,1b
3230:
324.endif
325
326.if RELOCATE_TO_RAM
327 /* we could be relocated by 32x or something else, adjust start addr */
328 lea (pc),a0
329 move.l a0,d0
330 and.l #0xff0000,d0
331 move.l d0,a0
332
333 /* copy, assume 8K size */
334 move.l #0xFF0100,a1
335 move.l (sizeof_bin,pc),d0
336 lsr.l #3,d0
3371:
338 move.l (a0)+,(a1)+
339 move.l (a0)+,(a1)+
340 dbra d0,1b
341
342 /* copy test code */
343 lea (test_code,pc),a0
344 move.l #0xffc000,a1
345 move.w #(test_code_end - test_code)/2-1,d0
3461:
347 move.w (a0)+,(a1)+
348 dbra d0,1b
349
350 lea (0f,pc),a0
351 move.l a0,d0
352 and.l #0x00ffff,d0
353 add.l #0xFF0100,d0
354 move.l d0,a0
355
356 /* patch test code */
357 move.l #0xffc000,a1
358 add.w #(test_code_ret_op-test_code+2),a1
359 move.l a0,(a1)
360
361 jmp (a0)
3620:
363.endif
364
365 movea.l #0,a6
366 move.l #0x8000,d7
367 moveq.l #0,d6
368
369 /* Init pads */
370 move.b #0x40,(0xa10009).l
371 move.b #0x40,(0xa10003).l
372
373 /* Initialize VDP */
374 jsr init_gfx
375
376 /* Clear h/v scroll */
377 movea.l #GFXDATA,a0
378 VRAM_ADDR 0x8000,(GFXCNTL)
379 move.l #0,(a0)
380 VSRAM_ADDR 0,(GFXCNTL)
381 move.l #0,(a0)
382
383 /* Load color data */
384 movea.l #0,a0
385 lea (colors,pc),a1
386 moveq.l #(colors_end-colors)/2,d0
387 jsr load_colors
388
389 /* load font patterns */
390 movea.l #GFXDATA,a0
391 lea (font,pc),a1
392 VRAM_ADDR 0,(GFXCNTL)
393 move.w #128*8,d3
394font_loop:
395 moveq.l #8-1,d2
396 moveq.l #0,d1
397 move.b (a1)+,d0
3980:
399 lsr.b #1,d0
400 roxl.l #1,d1
401 ror.l #5,d1
402 dbra d2,0b
403
404 rol.l #1,d1 /* fixup */
405 move.l d1,(a0)
406 dbra d3,font_loop
407
408 /* generate A layer map */
409 movea.l #0xe000,a1
410 move.l #28-1,d4
411lmaploop0:
412 movea.l a1,a0
413 jsr load_prepare
414
415 move.l #64/2-1,d3
4160: move.l #0x00000000,(a0)
417 dbra d3,0b
418
419 add.l #64*2,a1
420 dbra d4,lmaploop0
421
422 /* generate B layer map */
423 movea.l #0xc000,a0
424 jsr load_prepare
425
426 move.l #64*28/2-1,d3
4270: move.l #0x00000000,(a0)
428 dbra d3,0b
429
430 /* upload sprite data */
431 movea.l #0xfc00,a0
432 jsr load_prepare
433 lea (sprite_data,pc),a1
434
435 move.l #(sprite_data_end-sprite_data)/2-1,d3
4360: move.l (a1)+,(a0)
437 dbra d3,0b
438
439.if USE_VINT
440 /* wait for vsync before unmask */
441 jsr wait_vsync_poll
442
443 /* wait a bit to avoid nested vint */
444 move.w #20,d0
4450:
446 dbra d0,0b /* 10 cycles to go back */
447
448 /* enable and unmask vint */
449 write_vdp_r_dst 1,(VDP1_E_VBI | VDP1_E_DISPLAY | VDP1_MODE5),(GFXCNTL)
450 move.w #0x2000,sr
451.endif
452
453##################################################
454
455forever:
456.if USE_VINT
457 jsr wait_vsync
458.else
459 jsr wait_vsync_poll
460 jsr VBL
461.endif
462 bra forever
463
464
465INT:
466 /* let's hope VRAM is already set up.. */
467 lea (txt_exc,pc),a0
468 move.l #9,d0
469 move.l #27,d1
470 move.l #0xe000,d2
471 jsr print
472 bra forever
473
474##################################################
475
476VBL:
477 addq.b #1,d7
478# movem.l d0-d4/a0-a5,-(a7)
479
480 btst.b #5,(0xa10005).l
481 bne no_auto_transfer
482 change_mode MMODE_PC, MMODE_MAIN
483 write_vdp_r_dst 12,(VDP12_SCREEN_V224 | VDP12_SCREEN_H320 | VDP12_STE),(GFXCNTL)
484
485no_auto_transfer:
486 moveq.l #0,d0
487 move.w d7,d0
488 lsr.w #6,d0
489 and.w #0x1c,d0
490 lea (jumptab,pc,d0),a0
491 jmp (a0)
492jumptab:
493 /* branch insns here because we want to be position independent */
494 bra mode_main
495 bra mode_val_input
496 bra mode_edit_val /* edit val in editor */
497 bra mode_goto
498 bra mode_start_menu
499 bra mode_goto_predef
500 bra mode_jmp_addr
501 bra mode_transfer
502
503##################### main #######################
504
505mode_main:
506 /* assume we will hang */
507 lea (txt_dtack_err,pc),a0
508 move.l #9,d0
509 move.l #27,d1
510 move.l #0xe000,d2
511 jsr print
512
513 moveq.l #0,d1
514 move.l a6,d0
515 move.b d0,d1
516 lsr.l #8,d0
517 move.l d0,a1 /* current addr */
518 lsr.b #3,d1
519 neg.b d1
520 add.b #27-1,d1 /* line where the cursor sits */
521 swap d1
522
523 movea.l #0xe002,a2
524 move.l #27-1,d5 /* line counter for dbra */
525 or.l d1,d5
526
527draw_row:
528 move.l a2,a0
529 jsr load_prepare
530
531 btst.l #15,d7
532 beq 0f
533 move.w #' ',(a0)
5340:
535 /* addr */
536 move.l a1,d2
537 moveq.l #6,d3
538 jsr print_hex_preped
539
540 btst.l #4,d6
541 bne draw_row_safe
542
543 bsr get_safety_mask
544 cmp.b #0xf,d0
545 beq draw_row_safe
546
547# unsafe or partially safe
548draw_row_hsafe:
549 move.l d0,d4
550 swap d4 /* mask in upper word */
551 btst.l #15,d7
552 bne draw_row_hsafe_words_pre
553
554draw_row_hsafe_bytes_pre:
555 /* 8 bytes */
556 moveq.l #2,d3
557 move.w #3,d4
558
559draw_row_hsafe_bytes:
560 move.w #' ',(a0)
561 move.b d4,d0
562 add.b #16,d0
563 btst.l d0,d4
564 bne 0f
565 move.l #'?'|('?'<<16),(a0)
566 move.w #' ',(a0)
567 move.l #'?'|('?'<<16),(a0)
568 bra 1f
5690:
570 move.b (0,a1),d2
571 jsr print_hex_preped
572 move.w #' ',(a0)
573 move.b (1,a1),d2
574 jsr print_hex_preped
5751:
576 addq.l #2,a1
577 dbra d4,draw_row_hsafe_bytes
578
579 move.w #' ',(a0)
580
581 move.l d5,d0
582 swap d0
583 cmp.w d5,d0
584 beq draw_cursor_unsafe_byte
585 bra draw_chars_hsafe_pre
586
587draw_row_hsafe_words_pre:
588 /* 4 shorts */
589 moveq.l #4,d3
590 move.w #3,d4
591
592draw_row_hsafe_words:
593 move.w #' ',(a0)
594 move.b d4,d0
595 add.b #16,d0
596 btst.l d0,d4
597 bne 0f
598 move.l #'?'|('?'<<16),(a0)
599 move.l #'?'|('?'<<16),(a0)
600 bra 1f
6010:
602 move.w (a1),d2
603 jsr print_hex_preped
6041:
605 addq.l #2,a1
606 dbra d4,draw_row_hsafe_words
607
608 move.l #(' '<<16)|' ',(a0)
609
610 move.l d5,d0
611 swap d0
612 cmp.w d5,d0
613 beq draw_cursor_unsafe_word
614
615draw_chars_hsafe_pre:
616 subq.l #8,a1
617 move.w #3,d4
618 moveq.l #0,d0
619
620draw_chars_hsafe:
621 move.b d4,d0
622 add.b #16,d0
623 btst.l d0,d4
624 bne 0f
625 move.l #'?'|('?'<<16),(a0)
626 bra draw_chars_hsafe_next
6270:
628 btst.l #15,d7 /* must perform correct read type */
629 bne 0f /* doing byte reads on security reg hangs */
630 move.b (0,a1),d0
631 lsl.l #8,d0
632 move.b (1,a1),d0
633 bra 1f
6340:
635 move.w (a1),d0
6361:
637 ror.l #8,d0
638 move.b d0,d1
639 sub.b #0x20,d1
640 cmp.b #0x60,d1
641 blo 0f
642 move.b #'.',d0
6430:
644 move.w d0,(a0)
645
646 move.b #0,d0
647 rol.l #8,d0
648 move.b d0,d1
649 sub.b #0x20,d1
650 cmp.b #0x60,d1
651 blo 0f
652 move.b #'.',d0
6530:
654 move.w d0,(a0)
655
656draw_chars_hsafe_next:
657 addq.l #2,a1
658 dbra d4,draw_chars_hsafe
659
660 move.l #(' '<<16)|' ',(a0)
661 add.w #0x80,a2
662 dbra d5,draw_row
663 bra draw_status_bar
664
665
666# normal draw
667draw_row_safe:
668 btst.l #15,d7
669 bne draw_row_words
670
671draw_row_bytes:
672 /* 8 bytes */
673 moveq.l #2,d3
674 moveq.l #8-1,d4
675draw_bytes:
676 move.w #' ',(a0)
677 move.b (a1)+,d2
678 jsr print_hex_preped
679 dbra d4,draw_bytes
680
681 move.w #' ',(a0)
682
683 move.l d5,d0
684 swap d0
685 cmp.w d5,d0
686 beq draw_cursor_byte
687 bra draw_chars_pre
688
689draw_row_words:
690 /* 4 shorts */
691 moveq.l #4,d3
692 moveq.l #4-1,d4
693draw_words:
694 move.w #' ',(a0)
695 move.w (a1)+,d2
696 jsr print_hex_preped
697 dbra d4,draw_words
698
699 move.l #(' '<<16)|' ',(a0)
700
701 move.l d5,d0
702 swap d0
703 cmp.w d5,d0
704 beq draw_cursor_word
705
706draw_chars_pre:
707 /* 8 chars */
708 subq.l #8,a1
709 moveq.l #8-1,d4
710draw_chars:
711 move.b (a1)+,d0
712 move.b d0,d1
713 sub.b #0x20,d1
714 cmp.b #0x60,d1
715 blo 0f
716 move.w #'.',d0
7170:
718 move.w d0,(a0)
719 dbra d4,draw_chars
720
721 move.l #(' '<<16)|' ',(a0)
722
723 add.w #0x80,a2
724 dbra d5,draw_row
725
726
727draw_status_bar:
728 /* status bar */
729 move.l a2,a0
730 jsr load_prepare
731
732 btst.l #15,d7
733 beq 0f
734 move.w #' ',(a0)
7350:
736 mk_a6_addr d2
737 move.l #0x4006,d3
738 jsr print_hex_preped
739
740 /* clear error */
741 moveq.l #5-1,d0
7420:
743 move.l #' '|(' '<<16),(a0)
744 move.l #' '|(' '<<16),(a0)
745 dbra d0,0b
746
747
748 /* handle input */
749 jsr get_input /* x0cbrldu x1sa00du */
750
751 btst.l #16+4,d0 /* A - scroll modifier */
752 beq input_noa
753
754 do_dpad 16+0, sub.l, #0x0800
755 do_dpad 16+1, add.l, #0x0800
756 do_dpad 16+10, sub.l, #0xd800
757 do_dpad 16+11, add.l, #0xd800
758input_noa:
759 moveq.l #0,d1
760 move.w d7,d1
761 lsr.w #7,d1
762 lsr.w #7,d1
763
764 do_dpad 0, subq.l, #0x0008
765 do_dpad 1, addq.l, #0x0008
766 do_dpad 10, sub.l, d1
767 do_dpad 11, add.l, d1
768
769dpad_end:
770 /* update addr */
771 move.l a6,d1
772 cmp.b #0xf0,d1
773 blo 0f
774 sub.l #0xd800,a6
775 add.w #0x00d8,a6
776 bra 1f
7770:
778 cmp.b #0xd8,d1
779 blo 1f
780 add.l #0xd800,a6
781 sub.w #0x00d8,a6
7821:
783
784 /* other btns */
785 moveq.l #0,d1
786 btst.l #12,d0 /* B - switch byte/word mode */
787 beq input_nob
788 bclr.l #15,d7
789 add.w #0x4000,d7 /* changes between 01 10 */
790 move.l a6,d1
791 and.l #1,d1
792 sub.l d1,a6 /* make even, just in case */
793
794input_nob:
795 btst.l #13,d0 /* C - edit selected byte */
796 beq input_noc
797
798 change_mode MMODE_EDIT_VAL, MMODE_MAIN
799 write_vdp_r_dst 12,(VDP12_SCREEN_V224 | VDP12_SCREEN_H320 | VDP12_STE),(GFXCNTL)
800
801input_noc:
802 btst.l #5,d0 /* Start - menu */
803 beq input_nos
804
805 moveq.l #0,d5
806 change_mode MMODE_START_MENU, MMODE_MAIN
807 write_vdp_r_dst 12,(VDP12_SCREEN_V224 | VDP12_SCREEN_H320 | VDP12_STE),(GFXCNTL)
808
809input_nos:
810vbl_end:
811# movem.l (a7)+,d0-d4/a0-a5
812.if USE_VINT
813 rte
814.else
815 rts
816.endif
817
818
819draw_cursor_unsafe_byte:
820 move.l a6,d0
821 and.l #7,d0 /* byte offs */
822 move.b d0,d1
823 add.b d0,d0
824 add.b d1,d0 /* d0 *= 3 (chars) */
825 add.b d0,d0
826 lea (7*2,a2,d0),a0
827 jsr load_prepare
828 move.l #(0x2000|'?'|((0x2000|'?')<<16)),(a0)
829
830 move.l a2,a0
831 add.w #31*2,a0
832 jsr load_prepare /* restore a0 */
833 bra draw_chars_hsafe_pre
834
835draw_cursor_unsafe_word:
836 move.l a6,d0
837 and.l #7,d0 /* byte offs */
838 move.l d0,d1
839 lsr.b #1,d1 /* which word */
840 move.b d1,d2
841 lsl.b #2,d2
842 add.b d2,d1 /* num of chars to skip */
843 add.b d1,d1
844
845 lea (8*2,a2,d1),a0
846 jsr load_prepare
847 move.l #(0x2000|'?'|((0x2000|'?')<<16)),d0
848 move.l d0,(a0)
849 move.l d0,(a0)
850
851 move.l a2,a0
852 add.w #29*2,a0
853 jsr load_prepare /* restore a0 */
854 bra draw_chars_hsafe_pre
855
856
857draw_cursor_byte:
858 move.l a6,d0
859 and.l #7,d0 /* byte offs */
860 move.w #0x2002,d3
861
862 move.b (-8,a1,d0),d2
863 move.b d0,d1
864 add.b d0,d0
865 add.b d1,d0 /* d0 *= 3 (chars) */
866 add.b d0,d0
867 lea (7*2,a2,d0),a0
868 jsr load_prepare
869 jsr print_hex_preped
870
871 move.l a2,a0
872 add.w #31*2,a0
873 jsr load_prepare /* restore a0 */
874
875 bra draw_chars_pre
876
877draw_cursor_word:
878 move.l a6,d0
879 and.l #7,d0 /* byte offs */
880 move.l d0,d1
881 lsr.b #1,d1 /* which word */
882 move.b d1,d2
883 lsl.b #2,d2
884 add.b d2,d1 /* num of chars to skip */
885 add.b d1,d1
886 move.w #0x2004,d3
887
888 move.w (-8,a1,d0),d2
889 lea (8*2,a2,d1),a0
890 jsr load_prepare
891 jsr print_hex_preped
892
893 move.l a2,a0
894 add.w #29*2,a0
895 jsr load_prepare /* restore a0 */
896
897 bra draw_chars_pre
898
899
900#################### hedit #######################
901
902mode_edit_val:
903 btst.l #7,d6
904 bne mode_hedit_finish
905
906 /* read val to edit */
907 moveq.l #0,d5
908 mk_a6_addr d1
909 move.l d1,a0
910 btst.l #15,d7
911 bne 0f
912 move.b (a0),d5
913 lsl.l #8,d5
914 or.b #1,d5
915 bra 1f
9160:
917 move.w (a0),d5
918 lsl.l #8,d5
919 or.b #2,d5
9201:
921
922 change_mode MMODE_VAL_INPUT, MMODE_EDIT_VAL
923 bra vbl_end
924
925mode_hedit_finish:
926 /* write the val */
927 mk_a6_addr d1
928 move.l d1,a0
929 lsr.l #8,d5
930
931 btst.l #15,d7
932 bne 0f
933 move.b d5,(a0)
934 bra 1f
9350:
936 move.w d5,(a0)
9371:
938
939 bra return_to_main
940
941##################### goto #######################
942
943mode_goto:
944 btst.l #7,d6
945 bne mode_goto_finish
946
947 moveq.l #0,d5
948 swap d6
949 move.w d6,d5
950 swap d6
951 swap d5
952 or.b #3,d5 /* 3 bytes */
953 bclr.l #7,d6
954 change_mode MMODE_VAL_INPUT, MMODE_GOTO
955 bra vbl_end
956
957mode_goto_finish:
958 lsr.l #8,d5
959 move.l d5,d0
960 move.l d0,d1
961 and.l #7,d1
962 and.b #0xf8,d0
963 lsl.l #8,d0
964 or.l d1,d0
965 move.l d0,a6
966
967 lsr.l #8,d5
968 swap d6
969 move.w d5,d6
970 swap d6
971
972 bra return_to_main
973
974################### val edit #####################
975
976mode_val_input:
977 /* frame */
978 movea.l #0xe000+14*2+11*64*2,a1
979 moveq.l #6-1,d1
9800:
981 move.w a1,a0
982 jsr load_prepare
983 moveq.l #11-1,d0
9841:
985 move.w #0,(a0)
986 dbra d0,1b
987
988 add.w #64*2,a1
989 dbra d1,0b
990
991 /* text */
992 lea (txt_edit,pc),a0
993 move.l #15,d0
994 move.l #11,d1
995 move.l #0xc000,d2
996 jsr print
997
998 lea (txt_a_confirm,pc),a0
999 move.l #15,d0
1000 move.l #15,d1
1001 move.l #0xc000,d2
1002 jsr print
1003
1004 /* edit field */
1005 moveq.l #0,d0
1006 moveq.l #0,d1
1007 moveq.l #0,d3
1008 move.b d5,d3
1009 and.b #3,d3 /* edit field bytes */
1010
1011 move.b #19,d0
1012 sub.b d3,d0
1013 move.b #13,d1
1014 move.l d5,d2
1015 lsr.l #8,d2
1016 add.b d3,d3
1017 or.w #0x8000,d3
1018 jsr print_hex
1019
1020 /* current char */
1021 moveq.l #0,d0
1022 moveq.l #0,d1
1023
1024 and.w #6,d3
1025 move.b #19,d0
1026 move.b d3,d1
1027 lsr.b #1,d1 /* length in bytes */
1028 sub.b d1,d0
1029 move.b d5,d1
1030 lsr.b #2,d1
1031 and.b #7,d1 /* nibble to edit */
1032 add.b d1,d0
1033
1034 sub.b d1,d3
1035 sub.b #1,d3 /* chars to shift out */
1036 lsl.b #2,d3
1037 add.b #8,d3
1038 move.l d5,d2
1039 lsr.l d3,d2
1040
1041 move.b #13,d1
1042 move.w #0xa001,d3
1043 jsr print_hex
1044
1045 /* handle input */
1046 jsr get_input /* x0cbrldu x1sa00du */
1047
1048 move.w d0,d1
1049 and.w #0x0f00,d1
1050 beq ai_no_dpad
1051 move.b d5,d1
1052 and.b #3,d1
1053 add.b d1,d1 /* nibble count */
1054 sub.b #1,d1 /* max n.t.e. val */
1055 move.b d5,d2
1056 lsr.b #2,d2
1057 and.b #7,d2 /* nibble to edit */
1058
1059 move.b d0,d3
1060 and.b #3,d3
1061 beq ai_no_ud
1062 moveq.l #0,d3
1063 moveq.l #0,d4
1064 move.b #0xf,d3
1065 move.b #0x1,d4
1066 sub.b d2,d1
1067 lsl.b #2,d1
1068 add.b #8,d1
1069 lsl.l d1,d3 /* mask */
1070 lsl.l d1,d4 /* what to add/sub */
1071 move.l d5,d1
1072 and.l d3,d1
1073 btst.l #8,d0
1074 beq 0f
1075 add.l d4,d1
1076 bra 1f
10770:
1078 sub.l d4,d1
10791:
1080 and.l d3,d1
1081 eor.l #0xffffffff,d3
1082 and.l d3,d5
1083 or.l d1,d5
1084 bra vbl_end
1085
1086ai_no_ud:
1087 btst.l #10,d0
1088 bne 0f
1089 add.b #1,d2
1090 bra 1f
10910:
1092 sub.b #1,d2
10931:
1094 cmp.b #0,d2
1095 bge 0f
1096 move.b d1,d2
10970:
1098 cmp.b d1,d2
1099 ble 0f
1100 move.b #0,d2
11010:
1102 and.b #0xe3,d5
1103 lsl.b #2,d2
1104 or.b d2,d5
1105 bra vbl_end
1106
1107ai_no_dpad:
1108 move.w d0,d1
1109 and.w #0x1020,d1
1110 beq ai_no_sb
1111
1112 bra return_to_main
1113
1114ai_no_sb:
1115 btst.l #4,d0 /* A - confirm */
1116 beq ai_no_input
1117 bset.l #7,d6
1118 move.w d7,d1 /* back to prev mode */
1119 and.w #0x3800,d1
1120 lsr.w #3,d1
1121 and.w #0xc0ff,d7
1122 or.w d1,d7
1123
1124ai_no_input:
1125 bra vbl_end
1126
1127
1128################### start menu ###################
1129
1130mode_start_menu:
1131 /* frame */
1132 bsr start_menu_box
1133
1134 /* text */
1135 menu_text txt_about, 13, 9, 1
1136 menu_text txt_goto, 13, 11, 0
1137 menu_text txt_goto_predef, 13, 12, 0
1138 menu_text txt_jmp_addr, 13, 13, 0
1139 menu_text txt_dump, 13, 14, 0
1140 menu_text txt_dtack, 13, 15, 0
1141 menu_text txt_a_confirm, 13, 17, 2
1142
1143 /* dtack safety on/off */
1144 movea.l #0xe000+26*2+15*64*2,a0
1145 jsr load_prepare
1146 move.w #0x8000|'O',(a0)
1147 btst.l #4,d6
1148 bne 0f
1149 move.w #0x8000|'N',(a0)
1150 bra 1f
11510:
1152 move.w #0x8000|'F',(a0)
1153 move.w #0x8000|'F',(a0)
11541:
1155
1156 /* cursor */
1157 movea.l #0xe000+11*2+11*64*2,a0
1158 moveq.l #0,d0
1159 move.b d5,d0
1160 and.b #7,d0
1161 lsl.w #7,d0
1162 add.w d0,a0
1163 jsr load_prepare
1164 move.w #'>',(a0)
1165
1166 /* input */
1167 jsr get_input /* x0cbrldu x1sa00du */
1168
1169 move.w d0,d1
1170 and.w #3,d1
1171 beq msm_no_ud
1172 move.b d5,d1
1173 and.b #7,d1
1174 btst.l #0,d0
1175 sne d2
1176 or.b #1,d2 /* up -1, down 1 */
1177 add.b d2,d1
1178 cmp.b #0,d1
1179 bge 0f
1180 move.b #4,d1
11810:
1182 cmp.b #4,d1
1183 ble 0f
1184 move.b #0,d1
11850:
1186 and.b #0xf8,d5
1187 or.b d1,d5
1188 bra vbl_end
1189
1190msm_no_ud:
1191 btst.l #4,d0 /* A - confirm */
1192 beq msm_no_a
1193 move.b d5,d1
1194 and.b #7,d1
1195 bne 0f
1196 change_mode MMODE_GOTO, MMODE_MAIN
1197 bsr start_menu_box
1198 bra vbl_end
11990:
1200 cmp.b #1,d1
1201 bne 0f
1202 moveq.l #0,d5
1203 change_mode MMODE_GOTO_PREDEF, MMODE_MAIN
1204 bsr start_menu_box
1205 bra vbl_end
12060:
1207 cmp.b #2,d1
1208 bne 0f
1209 change_mode MMODE_JMP_ADDR, MMODE_MAIN
1210 bsr start_menu_box
1211 bra vbl_end
12120:
1213 cmp.b #3,d1
1214 bne 0f
1215 change_mode MMODE_PC, MMODE_MAIN
1216 bsr start_menu_box
1217 bra vbl_end
12180:
1219 cmp.b #4,d1
1220 bne 0f
1221 bchg.l #4,d6
1222 bra vbl_end
12230:
1224
1225msm_no_a:
1226 move.w d0,d1
1227 and.w #0x3000,d1
1228 beq msm_no_bc
1229 bra return_to_main
1230
1231msm_no_bc:
1232 bra vbl_end
1233
1234start_menu_box:
1235 movea.l #0xe000+10*2+8*64*2,a1
1236 move.w #11-1,d1
12370:
1238 move.w a1,a0
1239 jsr load_prepare
1240 move.w #20-1,d0
12411:
1242 move.w #0,(a0)
1243 dbra d0,1b
1244
1245 add.w #64*2,a1
1246 dbra d1,0b
1247 rts
1248
1249################### goto predef ##################
1250
1251mode_goto_predef:
1252 /* frame */
1253 movea.l #0xe000+14*2+8*64*2,a1
1254 move.l #predef_addr_cnt+2-1,d1
12550:
1256 move.w a1,a0
1257 jsr load_prepare
1258 moveq.l #10-1,d0
12591:
1260 move.w #0,(a0)
1261 dbra d0,1b
1262
1263 add.w #64*2,a1
1264 dbra d1,0b
1265
1266 /* draw addresses */
1267 movea.l #0xe000+17*2+9*64*2,a1
1268 lea (predef_addrs,pc),a2
1269 move.w #predef_addr_cnt-1,d4
1270 move.l #0x8006,d3
1271mgp_da_loop:
1272 move.w a1,a0
1273 jsr load_prepare
1274 move.l (a2)+,d2
1275 jsr print_hex_preped
1276 add.w #64*2,a1
1277 dbra d4,mgp_da_loop
1278
1279 /* cursor */
1280 movea.l #0xe000+15*2+9*64*2,a0
1281 moveq.l #0,d0
1282 move.b d5,d0
1283 lsl.w #7,d0
1284 add.w d0,a0
1285 jsr load_prepare
1286 move.w #'>',(a0)
1287
1288 /* input */
1289 jsr get_input /* x0cbrldu x1sa00du */
1290
1291 move.w d0,d1
1292 and.w #3,d1
1293 beq mgp_no_ud
1294 btst.l #0,d0
1295 sne d2
1296 or.b #1,d2 /* up -1, down 1 */
1297 add.b d2,d5
1298 cmp.b #0,d5
1299 bge 0f
1300 move.b #predef_addr_cnt-1,d5
13010:
1302 cmp.b #predef_addr_cnt-1,d5
1303 ble 0f
1304 move.b #0,d5
13050:
1306 bra vbl_end
1307
1308mgp_no_ud:
1309 btst.l #4,d0 /* A - confirm */
1310 beq mgp_no_a
1311 moveq.l #0,d0
1312 move.b d5,d0
1313 lsl.w #2,d0
1314 lea (predef_addrs,pc),a0
1315 move.l (a0,d0),d5
1316 lsl.l #8,d5
1317 bra mode_goto_finish
1318
1319mgp_no_a:
1320 move.w d0,d1
1321 and.w #0x3000,d1
1322 beq mgp_no_bc
1323 bra return_to_main
1324
1325mgp_no_bc:
1326 bra vbl_end
1327
1328##################### jmp ########################
1329
1330mode_jmp_addr:
1331 btst.l #7,d6
1332 bne mode_jmp_finish
1333
1334 moveq.l #0,d5
1335 or.b #3,d5 /* 3 bytes */
1336 bclr.l #7,d6
1337 change_mode MMODE_VAL_INPUT, MMODE_JMP_ADDR
1338 bra vbl_end
1339
1340mode_jmp_finish:
1341 lsr.l #8,d5
1342 write_vdp_r_dst 1,(VDP1_E_DISPLAY | VDP1_MODE5),(GFXCNTL) /* disable vint */
1343 move.l d5,a0
1344 jmp (a0)
1345
1346mode_transfer:
1347 move.b #0x40,(0xa1000b).l /* port 2 ctrl */
1348 move.b #0x00,(0xa10005).l /* port 2 data - start with TH low */
1349
1350 lea (txt_transfer_ready,pc),a0
1351 move.l #13,d0
1352 move.l #13,d1
1353 move.l #0x8000,d2
1354 jsr print
1355
1356wait_tl_low0:
1357 move.b (0xa10005),d0
1358 btst.b #4,d0
1359 bne wait_tl_low0
1360
1361 menu_text txt_working, 13, 13, 0
1362 bsr do_transfer
1363 bra return_to_main
1364
1365# go back to main mode
1366return_to_main:
1367 bclr.l #7,d6 /* not edited */
1368 change_mode MMODE_MAIN, MMODE_MAIN
1369 write_vdp_r_dst 12,(VDP12_SCREEN_V224 | VDP12_SCREEN_H320),(GFXCNTL)
1370 bra vbl_end
1371
1372
1373#################################################
1374# #
1375# Initialize VDP registers #
1376# #
1377#################################################
1378
1379init_gfx:
1380 move.l #GFXCNTL,a3
1381 write_vdp_reg 0,(VDP0_E_DISPLAY | VDP0_PLTT_FULL)
1382 write_vdp_reg 1,(VDP1_E_DISPLAY | VDP1_MODE5)
1383 write_vdp_reg 2,(0xe000 >> 10) /* Screen map a adress */
1384 write_vdp_reg 3,(0xe000 >> 10) /* Window address */
1385 write_vdp_reg 4,(0xc000 >> 13) /* Screen map b address */
1386 write_vdp_reg 5,(0xfc00 >> 9) /* Sprite address */
1387 write_vdp_reg 6,0
1388 write_vdp_reg 7,0 /* Backdrop color */
1389 write_vdp_reg 0x0a,1 /* Lines per hblank interrupt */
1390 write_vdp_reg 0x0b,0 /* 2-cell vertical scrolling */
1391 write_vdp_reg 0x0c,(VDP12_SCREEN_V224 | VDP12_SCREEN_H320)
1392 write_vdp_reg 0x0d,(0x8000 >> 10) /* Horizontal scroll address */
1393 write_vdp_reg 0x0e,0
1394 write_vdp_reg 0x0f,2
1395 write_vdp_reg 0x10,(VDP16_MAP_V32 | VDP16_MAP_H64) /* layer size */
1396 write_vdp_reg 0x11,0
1397 write_vdp_reg 0x12,0
1398 rts
1399
1400
1401# get mask of bits representing safe words
1402# a1 - address to check
1403# destroys d0-d2, strips upper bits from a1
1404get_safety_mask:
1405 move.l a1,d1
1406 lsl.l #8,d1
1407 lsr.l #8,d1
1408 lea (safe_addrs,pc),a1
1409 move.w #(safe_addrs_end - safe_addrs)/8-1,d2
1410 cmp.l #0x4D415253,(0xa130ec) /* 'MARS' */
1411 bne no_32x
1412 move.w #(safe_addrs_end_32x - safe_addrs)/8-1,d2
1413 move.w (0xa15100),d0
1414 and.w #3,d0
1415 cmp.w #3,d0 /* ADEN and nRES */
1416 bne no_32x_vdp
1417 btst.b #7,d0 /* FM */
1418 bne no_32x_vdp
1419 move.w #(safe_addrs_end_32x_vdp - safe_addrs)/8-1,d2
1420no_32x_vdp:
1421no_32x:
1422
14230:
1424 move.l (a1)+,d0
1425 cmp.l d0,d1
1426 blt 1f
1427 move.l (a1),d0
1428 cmp.l d0,d1
1429 ble addr_safe
14301:
1431 addq.l #4,a1
1432 dbra d2,0b
1433
1434 move.l d1,a1
1435
1436 moveq.l #0x0c,d0
1437 cmp.l #0xa14000,d1
1438 beq gsm_rts
1439
1440 moveq.l #0x08,d0
1441 cmp.l #0xa14100,d1
1442 beq gsm_rts
1443
1444 /* check for VDP address */
1445 move.l d1,d0
1446 swap d0
1447 and.b #0xe0,d0
1448 cmp.b #0xc0,d0
1449 bne addr_unsafe /* not vdp */
1450
1451 move.l d1,d0
1452 and.l #0x0700e0,d0
1453 bne addr_unsafe
1454
1455 move.l d1,d0
1456 and.b #0x1f,d0
1457 cmp.b #0x04,d0
1458 blt addr_hsafe_3 /* data port */
1459 cmp.b #0x10,d0
1460 blt addr_safe /* below PSG */
1461 cmp.b #0x18,d0
1462 bge addr_safe /* above PSG */
1463
1464addr_unsafe:
1465 moveq.l #0,d0 /* skip line */
1466 rts
1467
1468addr_hsafe_3:
1469 moveq.l #3,d0 /* skip 2 words */
1470 rts
1471
1472addr_safe:
1473 move.l d1,a1
1474 moveq.l #0xf,d0
1475gsm_rts:
1476 rts
1477
1478
1479# read single phase from controller
1480# #a0 - addr
1481# d0 - result
1482# destroys d1,d2
1483get_input:
1484 move.b #0x40,(0xa10003)
1485 nop
1486 nop
1487 nop
1488 move.b (0xa10003),d0
1489 move.b #0x00,(0xa10003)
1490 lsl.w #8,d0
1491 nop
1492 move.b (0xa10003),d0
1493 eor.w #0xffff,d0
1494
1495 swap d7
1496 move.w d7,d1
1497 eor.w d0,d1 /* changed btns */
1498 move.w d0,d7 /* old val */
1499 swap d7
1500 and.w d0,d1 /* what changed now */
1501 bne 0f
1502
1503 addq.b #1,d6
1504 move.b d6,d2
1505 and.b #0x0f,d2 /* do autorepeat */
1506 cmp.b #9,d2
1507 bne 1f
1508 move.w d0,d1
15090:
1510 and.b #0xf0,d6
15111:
1512 swap d0
1513 move.w d1,d0
1514 rts
1515
1516# Prepare to write to VDP RAM @a0
1517# sets a0 to VDP data port for convenience
1518# a0: VRAM base
1519# destroys d0
1520
1521load_prepare:
1522 VRAM_ADDR_var a0
1523 move.l d0,(GFXCNTL).l
1524 move.l #GFXDATA,a0
1525 rts
1526
1527
1528# Load color data from ROM
1529# a0: CRAM base
1530# a1: color list address
1531# d0: number of colors to load
1532# destroys d1
1533
1534load_colors:
1535 move.l d0,d1
1536 CRAM_ADDR_var a0
1537 move.l d0,(GFXCNTL).l
1538
1539 move.l #GFXDATA,a0
1540 subq.w #1,d1
15410:
1542 move.w (a1)+,(a0)
1543 dbra d1,0b
1544
1545 rts
1546
1547
1548# print
1549# a0 - string
1550# d0 - x
1551# d1 - y
1552# d2 - tile_bits[15:11]
1553# destroys a1
1554
1555print:
1556 move.l a0,a1
1557 XY2NT
1558 jsr load_prepare
1559 move.l d2,d0
1560 and.w #0xf800,d0
1561
1562_print_loop:
1563 move.b (a1)+,d0
1564 beq _print_end
1565
1566 move.w d0,(a0)
1567 bra _print_loop
1568
1569_print_end:
1570 rts
1571
1572
1573# print_hex
1574# d0 - x
1575# d1 - y
1576# d2 - value
1577# d3 - tile_bits[15:11]|digit_cnt[7:0]
1578# destroys a0, preserves d3
1579
1580print_hex:
1581 XY2NT
1582 jsr load_prepare
1583
1584print_hex_preped:
1585 moveq.l #0,d0
1586 move.b d3,d0
1587 move.l d0,d1
1588 lsl.b #2,d0
1589 ror.l d0,d2 /* prep value */
1590 subq.l #1,d1 /* count */
1591 move.w d3,d0
1592 and.w #0xf800,d0 /* keep upper bits in d0 */
1593
1594_print_hex_loop:
1595 rol.l #4,d2
1596 move.b d2,d0
1597 and.b #0xf,d0
1598
1599 add.b #'0',d0
1600 cmp.b #'9',d0
1601 ble 0f
1602 addq.b #7,d0
16030:
1604 move.w d0,(a0)
1605 dbra d1,_print_hex_loop
1606
1607 rts
1608
1609
1610# wait vertical sync interrupt
1611
1612wait_vsync:
1613 move.b d7,d0
1614_wait_change:
1615 stop #0x2000
1616 cmp.b d7,d0
1617 beq _wait_change
1618 rts
1619
1620
1621# wait vsync start (polling)
1622# destroys a0,d0
1623
1624wait_vsync_poll:
1625 move.l #GFXCNTL,a0
16260:
1627 move.w (a0),d0
1628 and.b #8,d0
1629 nop
1630 nop
1631 bne 0b
16320:
1633 move.w (a0),d0
1634 and.b #8,d0
1635 nop
1636 nop
1637 beq 0b
1638 rts
1639
1640
1641test_code:
1642 nop
1643
1644test_code_ret_op:
1645 jmp 0x123456 /* will be patched */
1646test_code_end:
1647
1648#################################################
1649# #
1650# RAM DATA #
1651# #
1652#################################################
1653
1654.bss
1655
1656# nothing :)
1657
1658.end
1659
1660# vim:filetype=asmM68k
Genesis/MegaDrive related projects