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hexed: vram transfer + early pc transfers
[megadrive.git] / hexed / hexed.s
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74d5977b 1###############################################################################
2#
f28eaaad 3# Copyright (c) 2009,2011 GraÅžvydas Ignotas
74d5977b 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#
f28eaaad 17# THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND ANY
74d5977b 18# EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
f28eaaad 20# DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY
74d5977b 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#
4db6e09f 31
ff17c043 32.equ USE_VINT, 0
33.equ COPY_TO_EXP, 1
34.equ RELOCATE_TO_RAM, 1
318e20ff 35
4db6e09f 36.text
37.globl main
d4279640 38.globl INT
1286a1ba 39.globl VBL
8689c962 40.globl return_to_main
4db6e09f 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
d90ff128 61.equ VDP1_MODE5, 0x04
4db6e09f 62
fbad1b76 63.equ VDP12_STE, 0x08
4db6e09f 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
4dfddc2f 78.equ MMODE_MAIN, 0
79.equ MMODE_VAL_INPUT, 1
80.equ MMODE_EDIT_VAL, 2
81.equ MMODE_GOTO, 3
27d5cc88 82.equ MMODE_START_MENU, 4
83.equ MMODE_GOTO_PREDEF, 5
d90ff128 84.equ MMODE_JMP_ADDR, 6
8689c962 85.equ MMODE_PC, 7
4db6e09f 86
27d5cc88 87.equ predef_addr_cnt, ((predef_addrs_end-predef_addrs)/4)
4db6e09f 88
89##################################################
90# #
91# MACROS #
92# #
93##################################################
94
95
27d5cc88 96# Write val to VDP register reg
97.macro write_vdp_r_dst reg val dst
98 move.w #((\reg << 8) + 0x8000 + \val),\dst
4db6e09f 99.endm
100
27d5cc88 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
4db6e09f 105
d90ff128 106# Set up address in VDP, control port in dst
107.macro VRAM_ADDR adr dst
80560599 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
0fc4f06b 113.endm
114
115
116# make VDP word from address adr and store in d0
117.macro XRAM_ADDR_var adr
570c4371 118 move.l \adr,d0
0fc4f06b 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
4db6e09f 124.endm
125
126
0fc4f06b 127.macro VRAM_ADDR_var adr
128 XRAM_ADDR_var \adr
129 or.l #0x40000000,d0
4db6e09f 130.endm
131
132
0fc4f06b 133.macro CRAM_ADDR_var adr
134 XRAM_ADDR_var \adr
135 or.l #0xc0000000,d0
4db6e09f 136.endm
137
138
1286a1ba 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
4276cd7a 148# check if some d-pad button (and modifier) is pressed
fbad1b76 149.macro do_dpad bit op val
150 btst.l #\bit,d0
151 beq 0f
152 \op.l \val,a6
153 bra dpad_end
4276cd7a 1540:
4276cd7a 155.endm
156
4dfddc2f 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
80560599 172# destroys a0,d0-d2
27d5cc88 173.macro menu_text str x y pal
318e20ff 174 lea (\str,pc),a0
27d5cc88 175 move.l #\x,d0
176 move.l #\y,d1
177 move.l #0x8000|(\pal<<13),d2
178 jsr print
179.endm
180
4db6e09f 181#################################################
182# #
183# DATA #
184# #
185#################################################
186
187colors:
4276cd7a 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
d4279640 194 dc.w 0x0000,0x044e,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000
195 dc.w 0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000
570c4371 196colors_end:
197
4db6e09f 198
199sprite_data:
200 /* Y size link attr X */
570c4371 201 dc.w 0; dc.b 0x05; dc.b 0; dc.w 0x6002; dc.w 0
4db6e09f 202sprite_data_end:
203
27d5cc88 204predef_addrs:
205 dc.l 0x000000, 0x200000, 0x400000, 0xa00000, 0xa10000
d4279640 206 dc.l 0xa11100, 0xa12000, 0xa13000, 0xa14000, 0xc00000
27d5cc88 207predef_addrs_end:
208
209safe_addrs:
210 dc.l 0x000000, 0x7fffff
211 dc.l 0xe00000, 0xffffff
d4279640 212 dc.l 0xa00000, 0xa100ff
213 dc.l 0xa11000, 0xa113ff
214 dc.l 0xa12000, 0xa120ff
215 dc.l 0xa13000, 0xa130ff
27d5cc88 216safe_addrs_end:
217
6f93f411 218sizeof_bin:
219 dc.l _edata
220
4dfddc2f 221txt_edit:
222 .ascii "- edit -\0"
223txt_a_confirm:
224 .ascii "A-confirm\0"
27d5cc88 225txt_about:
318e20ff 226 .ascii "hexed r2\0"
27d5cc88 227txt_goto:
228 .ascii "Go to address\0"
229txt_goto_predef:
230 .ascii "Go to (predef)\0"
d90ff128 231txt_jmp_addr:
232 .ascii "Jump to address\0"
80560599 233txt_dump:
8689c962 234 .ascii "PC Transfer\0"
27d5cc88 235txt_dtack:
236 .ascii "DTACK safety\0"
8689c962 237txt_transfer_ready:
238 .ascii "Transfer Ready\0"
80560599 239txt_working:
8689c962 240 .ascii "PC mode \0"
d4279640 241txt_dtack_err:
242 .ascii "DTACK err?\0"
243txt_exc:
244 .ascii "Exception \0"
4dfddc2f 245
4db6e09f 246##################################################
247# #
248# MAIN PROGRAM #
249# #
250##################################################
27d5cc88 251
252# global regs:
253# a6 = page_start[31:8]|cursor_offs[7:0]
254# d7 = old_inputs[31:16]|edit_bytes[15:14]|g_mode_old[13:11]|g_mode[10:8]|irq_cnt[7:0]
255# d6 = edit_word_save[31:15]|edit_done[7]|no_dtack_detect[4]|autorep_cnt[3:0]
256# d5 = main: tmp
257# edit: edit_word[31:8]|edit_pos[4:2]|byte_cnt[1:0]
258# menu: sel
259
570c4371 260.align 2
261
4db6e09f 262main:
8689c962 263 /* make sure io port 2 is doing inputs */
264 move.b #0,(0xa1000b).l
8682b7ce 265 /* make sure irqs are masked */
1286a1ba 266 move.w #0x2700,sr
8682b7ce 267 /* take care of TMSS */
268 move.b (0xa10000).l,d0
269 andi.b #0x0f,d0
270 beq no_tmss
271 move.l #0x53454741,(0xa14000).l
272 /* want cart, not OS rom if cart pops in */
273 move.w #1,(0xa14100).l
274 /* touch VDP after TMSS setup? */
275 tst.w (0xc00004).l
276no_tmss:
1286a1ba 277
f0e06736 278 /* want to do early PC transfer (with RAM/VRAM intact and such)?
279 * also give time PC to see start condition */
280 move.l #0x2000,d0
2810: dbra d0,0b
282
283 move.l #0xa10005,a0
284 btst.b #5,(a0)
285 bne no_early_transfer
286move.b #1,(0)
287 move.b #0x40,(0xa1000b).l /* port 2 ctrl */
288 move.b #0x00,(a0) /* port 2 data - start with TH low */
289 move.l #0x2000,d0
2900:
291 btst.b #4,(a0)
292 beq do_early_transfer
293 dbra d0,0b
294
295move.b #2,(0)
296 move.b #0,(0xa1000b).l
297 bra no_early_transfer /* timeout */
298
299do_early_transfer:
300move.b #9,(0)
301 bsr do_transfer
302
303no_early_transfer:
304
ff17c043 305.if COPY_TO_EXP
80560599 306 /* copy to expansion device if magic number is set */
307 move.l #0x400000,a1
308 cmp.w #0x1234,(a1)
27d5cc88 309 bne 0f
310
80560599 311 move.l #0,a0
6f93f411 312 move.l (sizeof_bin,pc),d0
313 lsr.l #3,d0
80560599 3141:
315 move.l (a0)+,(a1)+
316 move.l (a0)+,(a1)+
317 dbra d0,1b
3180:
319.endif
320
321.if RELOCATE_TO_RAM
ff17c043 322 /* we could be relocated by 32x or something else, adjust start addr */
323 lea (pc),a0
324 move.l a0,d0
325 and.l #0xff0000,d0
326 move.l d0,a0
327
80560599 328 /* copy, assume 8K size */
318e20ff 329 move.l #0xFF0100,a1
6f93f411 330 move.l (sizeof_bin,pc),d0
331 lsr.l #3,d0
27d5cc88 3321:
318e20ff 333 move.l (a0)+,(a1)+
334 move.l (a0)+,(a1)+
27d5cc88 335 dbra d0,1b
80560599 336
ff17c043 337 /* copy test code */
338 lea (test_code,pc),a0
339 move.l #0xffc000,a1
340 move.w #(test_code_end - test_code)/2-1,d0
3411:
342 move.w (a0)+,(a1)+
343 dbra d0,1b
344
318e20ff 345 lea (0f,pc),a0
ff17c043 346 move.l a0,d0
347 and.l #0x00ffff,d0
348 add.l #0xFF0100,d0
349 move.l d0,a0
350
351 /* patch test code */
352 move.l #0xffc000,a1
353 add.w #(test_code_ret_op-test_code+2),a1
354 move.l a0,(a1)
355
318e20ff 356 jmp (a0)
27d5cc88 3570:
358.endif
359
1286a1ba 360 movea.l #0,a6
4dfddc2f 361 move.l #0x8000,d7
fbad1b76 362 moveq.l #0,d6
1286a1ba 363
364 /* Init pads */
365 move.b #0x40,(0xa10009).l
366 move.b #0x40,(0xa10003).l
367
4db6e09f 368 /* Initialize VDP */
369 jsr init_gfx
370
80560599 371 /* Clear h/v scroll */
372 movea.l #GFXDATA,a0
373 VRAM_ADDR 0x8000,(GFXCNTL)
374 move.l #0,(a0)
375 VSRAM_ADDR 0,(GFXCNTL)
376 move.l #0,(a0)
377
4db6e09f 378 /* Load color data */
0fc4f06b 379 movea.l #0,a0
318e20ff 380 lea (colors,pc),a1
0fc4f06b 381 moveq.l #(colors_end-colors)/2,d0
4db6e09f 382 jsr load_colors
383
d90ff128 384 /* load font patterns */
318e20ff 385 movea.l #GFXDATA,a0
386 lea (font,pc),a1
d90ff128 387 VRAM_ADDR 0,(GFXCNTL)
388 move.w #128*8,d3
389font_loop:
390 moveq.l #8-1,d2
391 moveq.l #0,d1
392 move.b (a1)+,d0
3930:
394 lsr.b #1,d0
395 roxl.l #1,d1
396 ror.l #5,d1
397 dbra d2,0b
398
399 rol.l #1,d1 /* fixup */
400 move.l d1,(a0)
401 dbra d3,font_loop
4db6e09f 402
403 /* generate A layer map */
1286a1ba 404 movea.l #0xe000,a1
4db6e09f 405 move.l #28-1,d4
406lmaploop0:
1286a1ba 407 movea.l a1,a0
4db6e09f 408 jsr load_prepare
409
570c4371 410 move.l #64/2-1,d3
0fc4f06b 4110: move.l #0x00000000,(a0)
4db6e09f 412 dbra d3,0b
413
1286a1ba 414 add.l #64*2,a1
4db6e09f 415 dbra d4,lmaploop0
416
417 /* generate B layer map */
0fc4f06b 418 movea.l #0xc000,a0
4db6e09f 419 jsr load_prepare
420
570c4371 421 move.l #64*28/2-1,d3
0fc4f06b 4220: move.l #0x00000000,(a0)
4db6e09f 423 dbra d3,0b
424
425 /* upload sprite data */
0fc4f06b 426 movea.l #0xfc00,a0
4db6e09f 427 jsr load_prepare
318e20ff 428 lea (sprite_data,pc),a1
4db6e09f 429
430 move.l #(sprite_data_end-sprite_data)/2-1,d3
0fc4f06b 4310: move.l (a1)+,(a0)
4db6e09f 432 dbra d3,0b
433
318e20ff 434.if USE_VINT
d4279640 435 /* wait for vsync before unmask */
318e20ff 436 jsr wait_vsync_poll
d4279640 437
74d5977b 438 /* wait a bit to avoid nested vint */
439 move.w #20,d0
4400:
441 dbra d0,0b /* 10 cycles to go back */
442
318e20ff 443 /* enable and unmask vint */
444 write_vdp_r_dst 1,(VDP1_E_VBI | VDP1_E_DISPLAY | VDP1_MODE5),(GFXCNTL)
74d5977b 445 move.w #0x2000,sr
318e20ff 446.endif
570c4371 447
4db6e09f 448##################################################
1286a1ba 449
4db6e09f 450forever:
318e20ff 451.if USE_VINT
4db6e09f 452 jsr wait_vsync
318e20ff 453.else
454 jsr wait_vsync_poll
455 jsr VBL
456.endif
4db6e09f 457 bra forever
4db6e09f 458
459
d4279640 460INT:
461 /* let's hope VRAM is already set up.. */
318e20ff 462 lea (txt_exc,pc),a0
d4279640 463 move.l #9,d0
464 move.l #27,d1
465 move.l #0xe000,d2
466 jsr print
467 bra forever
468
469##################################################
470
1286a1ba 471VBL:
fbad1b76 472 addq.b #1,d7
d90ff128 473# movem.l d0-d4/a0-a5,-(a7)
1286a1ba 474
8689c962 475 btst.b #5,(0xa10005).l
476 bne no_auto_transfer
477 change_mode MMODE_PC, MMODE_MAIN
478 write_vdp_r_dst 12,(VDP12_SCREEN_V224 | VDP12_SCREEN_H320 | VDP12_STE),(GFXCNTL)
479
480no_auto_transfer:
fbad1b76 481 moveq.l #0,d0
482 move.w d7,d0
483 lsr.w #6,d0
484 and.w #0x1c,d0
318e20ff 485 lea (jumptab,pc,d0),a0
fbad1b76 486 jmp (a0)
487jumptab:
272bd2ec 488 /* branch insns here because we want to be position independent */
318e20ff 489 bra mode_main
490 bra mode_val_input
491 bra mode_edit_val /* edit val in editor */
492 bra mode_goto
493 bra mode_start_menu
494 bra mode_goto_predef
495 bra mode_jmp_addr
80560599 496 bra mode_transfer
fbad1b76 497
498##################### main #######################
499
500mode_main:
d4279640 501 /* assume we will hang */
318e20ff 502 lea (txt_dtack_err,pc),a0
d4279640 503 move.l #9,d0
504 move.l #27,d1
505 move.l #0xe000,d2
506 jsr print
507
508 moveq.l #0,d1
1286a1ba 509 move.l a6,d0
4276cd7a 510 move.b d0,d1
1286a1ba 511 lsr.l #8,d0
512 move.l d0,a1 /* current addr */
4276cd7a 513 lsr.b #3,d1
514 neg.b d1
515 add.b #27-1,d1 /* line where the cursor sits */
516 swap d1
1286a1ba 517
27d5cc88 518 movea.l #0xe002,a2
4276cd7a 519 move.l #27-1,d5 /* line counter for dbra */
520 or.l d1,d5
1286a1ba 521
27d5cc88 522draw_row:
1286a1ba 523 move.l a2,a0
524 jsr load_prepare
525
27d5cc88 526 btst.l #15,d7
527 beq 0f
528 move.w #' ',(a0)
5290:
1286a1ba 530 /* addr */
531 move.l a1,d2
532 moveq.l #6,d3
533 jsr print_hex_preped
534
27d5cc88 535 btst.l #4,d6
536 bne draw_row_safe
537
d4279640 538 bsr get_safety_mask
539 cmp.b #0xf,d0
540 beq draw_row_safe
27d5cc88 541
d4279640 542# unsafe or partially safe
543draw_row_hsafe:
544 move.l d0,d4
545 swap d4 /* mask in upper word */
27d5cc88 546 btst.l #15,d7
d4279640 547 bne draw_row_hsafe_words_pre
27d5cc88 548
d4279640 549draw_row_hsafe_bytes_pre:
27d5cc88 550 /* 8 bytes */
d4279640 551 moveq.l #2,d3
552 move.w #3,d4
553
554draw_row_hsafe_bytes:
27d5cc88 555 move.w #' ',(a0)
d4279640 556 move.b d4,d0
557 add.b #16,d0
558 btst.l d0,d4
559 bne 0f
27d5cc88 560 move.l #'?'|('?'<<16),(a0)
d4279640 561 move.w #' ',(a0)
562 move.l #'?'|('?'<<16),(a0)
563 bra 1f
5640:
565 move.b (0,a1),d2
566 jsr print_hex_preped
567 move.w #' ',(a0)
568 move.b (1,a1),d2
569 jsr print_hex_preped
5701:
571 addq.l #2,a1
572 dbra d4,draw_row_hsafe_bytes
27d5cc88 573
574 move.w #' ',(a0)
575
576 move.l d5,d0
577 swap d0
578 cmp.w d5,d0
579 beq draw_cursor_unsafe_byte
d4279640 580 bra draw_chars_hsafe_pre
27d5cc88 581
d4279640 582draw_row_hsafe_words_pre:
27d5cc88 583 /* 4 shorts */
d4279640 584 moveq.l #4,d3
585 move.w #3,d4
586
587draw_row_hsafe_words:
27d5cc88 588 move.w #' ',(a0)
d4279640 589 move.b d4,d0
590 add.b #16,d0
591 btst.l d0,d4
592 bne 0f
27d5cc88 593 move.l #'?'|('?'<<16),(a0)
594 move.l #'?'|('?'<<16),(a0)
d4279640 595 bra 1f
5960:
597 move.w (a1),d2
598 jsr print_hex_preped
5991:
600 addq.l #2,a1
601 dbra d4,draw_row_hsafe_words
27d5cc88 602
603 move.l #(' '<<16)|' ',(a0)
604
605 move.l d5,d0
606 swap d0
607 cmp.w d5,d0
608 beq draw_cursor_unsafe_word
609
d4279640 610draw_chars_hsafe_pre:
611 subq.l #8,a1
612 move.w #3,d4
613 moveq.l #0,d0
614
615draw_chars_hsafe:
616 move.b d4,d0
617 add.b #16,d0
618 btst.l d0,d4
619 bne 0f
27d5cc88 620 move.l #'?'|('?'<<16),(a0)
d4279640 621 bra draw_chars_hsafe_next
6220:
623 btst.l #15,d7 /* must perform correct read type */
624 bne 0f /* doing byte reads on security reg hangs */
625 move.b (0,a1),d0
626 lsl.l #8,d0
627 move.b (1,a1),d0
628 bra 1f
6290:
630 move.w (a1),d0
6311:
632 ror.l #8,d0
633 move.b d0,d1
634 sub.b #0x20,d1
635 cmp.b #0x60,d1
636 blo 0f
637 move.b #'.',d0
6380:
639 move.w d0,(a0)
640
641 move.b #0,d0
642 rol.l #8,d0
643 move.b d0,d1
644 sub.b #0x20,d1
645 cmp.b #0x60,d1
646 blo 0f
647 move.b #'.',d0
6480:
649 move.w d0,(a0)
650
651draw_chars_hsafe_next:
652 addq.l #2,a1
653 dbra d4,draw_chars_hsafe
27d5cc88 654
655 move.l #(' '<<16)|' ',(a0)
27d5cc88 656 add.w #0x80,a2
657 dbra d5,draw_row
658 bra draw_status_bar
659
660
661# normal draw
662draw_row_safe:
663 btst.l #15,d7
664 bne draw_row_words
665
666draw_row_bytes:
667 /* 8 bytes */
668 moveq.l #2,d3
669 moveq.l #8-1,d4
670draw_bytes:
671 move.w #' ',(a0)
672 move.b (a1)+,d2
673 jsr print_hex_preped
674 dbra d4,draw_bytes
675
676 move.w #' ',(a0)
677
678 move.l d5,d0
679 swap d0
680 cmp.w d5,d0
681 beq draw_cursor_byte
682 bra draw_chars_pre
683
684draw_row_words:
1286a1ba 685 /* 4 shorts */
4276cd7a 686 moveq.l #4,d3
1286a1ba 687 moveq.l #4-1,d4
27d5cc88 688draw_words:
1286a1ba 689 move.w #' ',(a0)
690 move.w (a1)+,d2
1286a1ba 691 jsr print_hex_preped
27d5cc88 692 dbra d4,draw_words
693
694 move.l #(' '<<16)|' ',(a0)
1286a1ba 695
4276cd7a 696 move.l d5,d0
697 swap d0
698 cmp.w d5,d0
27d5cc88 699 beq draw_cursor_word
4276cd7a 700
701draw_chars_pre:
1286a1ba 702 /* 8 chars */
703 subq.l #8,a1
704 moveq.l #8-1,d4
705draw_chars:
706 move.b (a1)+,d0
707 move.b d0,d1
708 sub.b #0x20,d1
709 cmp.b #0x60,d1
710 blo 0f
711 move.w #'.',d0
7120:
713 move.w d0,(a0)
714 dbra d4,draw_chars
715
27d5cc88 716 move.l #(' '<<16)|' ',(a0)
717
1286a1ba 718 add.w #0x80,a2
27d5cc88 719 dbra d5,draw_row
1286a1ba 720
d4279640 721
27d5cc88 722draw_status_bar:
4276cd7a 723 /* status bar */
27d5cc88 724 move.l a2,a0
4276cd7a 725 jsr load_prepare
27d5cc88 726
727 btst.l #15,d7
728 beq 0f
729 move.w #' ',(a0)
7300:
4dfddc2f 731 mk_a6_addr d2
4276cd7a 732 move.l #0x4006,d3
733 jsr print_hex_preped
d4279640 734
735 /* clear error */
736 moveq.l #5-1,d0
7370:
738 move.l #' '|(' '<<16),(a0)
739 move.l #' '|(' '<<16),(a0)
740 dbra d0,0b
741
4276cd7a 742
1286a1ba 743 /* handle input */
744 jsr get_input /* x0cbrldu x1sa00du */
1286a1ba 745
fbad1b76 746 btst.l #16+4,d0 /* A - scroll modifier */
747 beq input_noa
748
749 do_dpad 16+0, sub, #0x0800
750 do_dpad 16+1, add, #0x0800
751 do_dpad 16+10, sub, #0xd800
752 do_dpad 16+11, add, #0xd800
753input_noa:
754 moveq.l #0,d1
4dfddc2f 755 move.w d7,d1
756 lsr.w #7,d1
757 lsr.w #7,d1
fbad1b76 758
759 do_dpad 0, subq, #0x0008
760 do_dpad 1, addq, #0x0008
761 do_dpad 10, sub, d1
762 do_dpad 11, add, d1
763
764dpad_end:
4dfddc2f 765 /* update addr */
766 move.l a6,d1
767 cmp.b #0xf0,d1
768 blo 0f
769 sub.l #0xd800,a6
770 add.w #0x00d8,a6
771 bra 1f
7720:
773 cmp.b #0xd8,d1
774 blo 1f
775 add.l #0xd800,a6
776 sub.w #0x00d8,a6
7771:
778
779 /* other btns */
fbad1b76 780 moveq.l #0,d1
781 btst.l #12,d0 /* B - switch byte/word mode */
782 beq input_nob
4dfddc2f 783 bclr.l #15,d7
784 add.w #0x4000,d7 /* changes between 01 10 */
fbad1b76 785 move.l a6,d1
786 and.l #1,d1
787 sub.l d1,a6 /* make even, just in case */
788
789input_nob:
790 btst.l #13,d0 /* C - edit selected byte */
791 beq input_noc
4dfddc2f 792
793 change_mode MMODE_EDIT_VAL, MMODE_MAIN
27d5cc88 794 write_vdp_r_dst 12,(VDP12_SCREEN_V224 | VDP12_SCREEN_H320 | VDP12_STE),(GFXCNTL)
fbad1b76 795
796input_noc:
27d5cc88 797 btst.l #5,d0 /* Start - menu */
4dfddc2f 798 beq input_nos
799
27d5cc88 800 moveq.l #0,d5
801 change_mode MMODE_START_MENU, MMODE_MAIN
802 write_vdp_r_dst 12,(VDP12_SCREEN_V224 | VDP12_SCREEN_H320 | VDP12_STE),(GFXCNTL)
1286a1ba 803
4dfddc2f 804input_nos:
fbad1b76 805vbl_end:
d90ff128 806# movem.l (a7)+,d0-d4/a0-a5
318e20ff 807.if USE_VINT
1286a1ba 808 rte
318e20ff 809.else
810 rts
811.endif
1286a1ba 812
813
27d5cc88 814draw_cursor_unsafe_byte:
815 move.l a6,d0
816 and.l #7,d0 /* byte offs */
817 move.b d0,d1
818 add.b d0,d0
819 add.b d1,d0 /* d0 *= 3 (chars) */
820 add.b d0,d0
821 lea (7*2,a2,d0),a0
822 jsr load_prepare
823 move.l #(0x2000|'?'|((0x2000|'?')<<16)),(a0)
824
825 move.l a2,a0
826 add.w #31*2,a0
827 jsr load_prepare /* restore a0 */
318e20ff 828 bra draw_chars_hsafe_pre
27d5cc88 829
830draw_cursor_unsafe_word:
4276cd7a 831 move.l a6,d0
832 and.l #7,d0 /* byte offs */
833 move.l d0,d1
834 lsr.b #1,d1 /* which word */
835 move.b d1,d2
836 lsl.b #2,d2
837 add.b d2,d1 /* num of chars to skip */
27d5cc88 838 add.b d1,d1
839
840 lea (8*2,a2,d1),a0
841 jsr load_prepare
842 move.l #(0x2000|'?'|((0x2000|'?')<<16)),d0
843 move.l d0,(a0)
844 move.l d0,(a0)
845
846 move.l a2,a0
847 add.w #29*2,a0
848 jsr load_prepare /* restore a0 */
318e20ff 849 bra draw_chars_hsafe_pre
4276cd7a 850
4276cd7a 851
fbad1b76 852draw_cursor_byte:
27d5cc88 853 move.l a6,d0
854 and.l #7,d0 /* byte offs */
855 move.w #0x2002,d3
856
fbad1b76 857 move.b (-8,a1,d0),d2
27d5cc88 858 move.b d0,d1
859 add.b d0,d0
860 add.b d1,d0 /* d0 *= 3 (chars) */
861 add.b d0,d0
862 lea (7*2,a2,d0),a0
863 jsr load_prepare
864 jsr print_hex_preped
865
866 move.l a2,a0
867 add.w #31*2,a0
868 jsr load_prepare /* restore a0 */
869
318e20ff 870 bra draw_chars_pre
fbad1b76 871
872draw_cursor_word:
27d5cc88 873 move.l a6,d0
874 and.l #7,d0 /* byte offs */
875 move.l d0,d1
876 lsr.b #1,d1 /* which word */
877 move.b d1,d2
878 lsl.b #2,d2
879 add.b d2,d1 /* num of chars to skip */
880 add.b d1,d1
881 move.w #0x2004,d3
882
fbad1b76 883 move.w (-8,a1,d0),d2
27d5cc88 884 lea (8*2,a2,d1),a0
4276cd7a 885 jsr load_prepare
4276cd7a 886 jsr print_hex_preped
887
888 move.l a2,a0
27d5cc88 889 add.w #29*2,a0
4276cd7a 890 jsr load_prepare /* restore a0 */
891
318e20ff 892 bra draw_chars_pre
4276cd7a 893
894
4dfddc2f 895#################### hedit #######################
896
897mode_edit_val:
898 btst.l #7,d6
899 bne mode_hedit_finish
900
901 /* read val to edit */
5f6473d9 902 moveq.l #0,d5
4dfddc2f 903 mk_a6_addr d1
904 move.l d1,a0
4dfddc2f 905 btst.l #15,d7
906 bne 0f
5f6473d9 907 move.b (a0),d5
908 lsl.l #8,d5
909 or.b #1,d5
4dfddc2f 910 bra 1f
9110:
5f6473d9 912 move.w (a0),d5
913 lsl.l #8,d5
914 or.b #2,d5
4dfddc2f 9151:
4dfddc2f 916
4dfddc2f 917 change_mode MMODE_VAL_INPUT, MMODE_EDIT_VAL
318e20ff 918 bra vbl_end
4dfddc2f 919
920mode_hedit_finish:
921 /* write the val */
922 mk_a6_addr d1
923 move.l d1,a0
5f6473d9 924 lsr.l #8,d5
4dfddc2f 925
926 btst.l #15,d7
927 bne 0f
5f6473d9 928 move.b d5,(a0)
4dfddc2f 929 bra 1f
9300:
5f6473d9 931 move.w d5,(a0)
4dfddc2f 9321:
933
4dfddc2f 934 bra return_to_main
935
936##################### goto #######################
937
938mode_goto:
939 btst.l #7,d6
940 bne mode_goto_finish
fbad1b76 941
5f6473d9 942 moveq.l #0,d5
943 swap d6
944 move.w d6,d5
945 swap d6
946 swap d5
947 or.b #3,d5 /* 3 bytes */
4dfddc2f 948 bclr.l #7,d6
949 change_mode MMODE_VAL_INPUT, MMODE_GOTO
318e20ff 950 bra vbl_end
4dfddc2f 951
952mode_goto_finish:
5f6473d9 953 lsr.l #8,d5
954 move.l d5,d0
4dfddc2f 955 move.l d0,d1
956 and.l #7,d1
957 and.b #0xf8,d0
958 lsl.l #8,d0
959 or.l d1,d0
960 move.l d0,a6
961
5f6473d9 962 lsr.l #8,d5
963 swap d6
964 move.w d5,d6
965 swap d6
966
4dfddc2f 967 bra return_to_main
968
969################### val edit #####################
970
971mode_val_input:
972 /* frame */
973 movea.l #0xe000+14*2+11*64*2,a1
974 moveq.l #6-1,d1
9750:
976 move.w a1,a0
977 jsr load_prepare
978 moveq.l #11-1,d0
9791:
980 move.w #0,(a0)
981 dbra d0,1b
982
983 add.w #64*2,a1
984 dbra d1,0b
985
986 /* text */
318e20ff 987 lea (txt_edit,pc),a0
4dfddc2f 988 move.l #15,d0
989 move.l #11,d1
990 move.l #0xc000,d2
991 jsr print
992
318e20ff 993 lea (txt_a_confirm,pc),a0
4dfddc2f 994 move.l #15,d0
995 move.l #15,d1
996 move.l #0xc000,d2
997 jsr print
998
999 /* edit field */
1000 moveq.l #0,d0
1001 moveq.l #0,d1
1002 moveq.l #0,d3
5f6473d9 1003 move.b d5,d3
1004 and.b #3,d3 /* edit field bytes */
4dfddc2f 1005
1006 move.b #19,d0
1007 sub.b d3,d0
1008 move.b #13,d1
5f6473d9 1009 move.l d5,d2
4dfddc2f 1010 lsr.l #8,d2
1011 add.b d3,d3
1012 or.w #0x8000,d3
1013 jsr print_hex
1014
1015 /* current char */
1016 moveq.l #0,d0
1017 moveq.l #0,d1
1018
1019 and.w #6,d3
1020 move.b #19,d0
1021 move.b d3,d1
1022 lsr.b #1,d1 /* length in bytes */
1023 sub.b d1,d0
5f6473d9 1024 move.b d5,d1
1025 lsr.b #2,d1
4dfddc2f 1026 and.b #7,d1 /* nibble to edit */
1027 add.b d1,d0
1028
1029 sub.b d1,d3
1030 sub.b #1,d3 /* chars to shift out */
1031 lsl.b #2,d3
1032 add.b #8,d3
5f6473d9 1033 move.l d5,d2
4dfddc2f 1034 lsr.l d3,d2
1035
1036 move.b #13,d1
1037 move.w #0xa001,d3
1038 jsr print_hex
1039
1040 /* handle input */
1041 jsr get_input /* x0cbrldu x1sa00du */
1042
1043 move.w d0,d1
1044 and.w #0x0f00,d1
1045 beq ai_no_dpad
5f6473d9 1046 move.b d5,d1
1047 and.b #3,d1
4dfddc2f 1048 add.b d1,d1 /* nibble count */
1049 sub.b #1,d1 /* max n.t.e. val */
5f6473d9 1050 move.b d5,d2
1051 lsr.b #2,d2
4dfddc2f 1052 and.b #7,d2 /* nibble to edit */
1053
1054 move.b d0,d3
1055 and.b #3,d3
1056 beq ai_no_ud
1057 moveq.l #0,d3
1058 moveq.l #0,d4
1059 move.b #0xf,d3
1060 move.b #0x1,d4
1061 sub.b d2,d1
1062 lsl.b #2,d1
1063 add.b #8,d1
1064 lsl.l d1,d3 /* mask */
1065 lsl.l d1,d4 /* what to add/sub */
5f6473d9 1066 move.l d5,d1
4dfddc2f 1067 and.l d3,d1
1068 btst.l #8,d0
1069 beq 0f
1070 add.l d4,d1
1071 bra 1f
10720:
1073 sub.l d4,d1
10741:
1075 and.l d3,d1
1076 eor.l #0xffffffff,d3
5f6473d9 1077 and.l d3,d5
1078 or.l d1,d5
318e20ff 1079 bra vbl_end
4dfddc2f 1080
1081ai_no_ud:
1082 btst.l #10,d0
1083 bne 0f
1084 add.b #1,d2
1085 bra 1f
10860:
1087 sub.b #1,d2
10881:
1089 cmp.b #0,d2
1090 bge 0f
1091 move.b d1,d2
10920:
1093 cmp.b d1,d2
1094 ble 0f
1095 move.b #0,d2
10960:
5f6473d9 1097 and.b #0xe3,d5
1098 lsl.b #2,d2
1099 or.b d2,d5
318e20ff 1100 bra vbl_end
4dfddc2f 1101
1102ai_no_dpad:
1103 move.w d0,d1
1104 and.w #0x1020,d1
1105 beq ai_no_sb
1106
4dfddc2f 1107 bra return_to_main
1108
1109ai_no_sb:
5f6473d9 1110 btst.l #4,d0 /* A - confirm */
4dfddc2f 1111 beq ai_no_input
1112 bset.l #7,d6
5f6473d9 1113 move.w d7,d1 /* back to prev mode */
4dfddc2f 1114 and.w #0x3800,d1
1115 lsr.w #3,d1
1116 and.w #0xc0ff,d7
1117 or.w d1,d7
1118
1119ai_no_input:
318e20ff 1120 bra vbl_end
4dfddc2f 1121
1122
27d5cc88 1123################### start menu ###################
1124
1125mode_start_menu:
1126 /* frame */
1127 bsr start_menu_box
1128
1129 /* text */
1130 menu_text txt_about, 13, 9, 1
1131 menu_text txt_goto, 13, 11, 0
1132 menu_text txt_goto_predef, 13, 12, 0
d90ff128 1133 menu_text txt_jmp_addr, 13, 13, 0
80560599 1134 menu_text txt_dump, 13, 14, 0
1135 menu_text txt_dtack, 13, 15, 0
1136 menu_text txt_a_confirm, 13, 17, 2
27d5cc88 1137
1138 /* dtack safety on/off */
80560599 1139 movea.l #0xe000+26*2+15*64*2,a0
27d5cc88 1140 jsr load_prepare
1141 move.w #0x8000|'O',(a0)
1142 btst.l #4,d6
1143 bne 0f
1144 move.w #0x8000|'N',(a0)
1145 bra 1f
11460:
1147 move.w #0x8000|'F',(a0)
1148 move.w #0x8000|'F',(a0)
11491:
1150
1151 /* cursor */
1152 movea.l #0xe000+11*2+11*64*2,a0
1153 moveq.l #0,d0
1154 move.b d5,d0
80560599 1155 and.b #7,d0
27d5cc88 1156 lsl.w #7,d0
1157 add.w d0,a0
1158 jsr load_prepare
1159 move.w #'>',(a0)
1160
1161 /* input */
1162 jsr get_input /* x0cbrldu x1sa00du */
1163
1164 move.w d0,d1
1165 and.w #3,d1
1166 beq msm_no_ud
1167 move.b d5,d1
80560599 1168 and.b #7,d1
27d5cc88 1169 btst.l #0,d0
1170 sne d2
1171 or.b #1,d2 /* up -1, down 1 */
1172 add.b d2,d1
1173 cmp.b #0,d1
1174 bge 0f
80560599 1175 move.b #4,d1
27d5cc88 11760:
80560599 1177 cmp.b #4,d1
27d5cc88 1178 ble 0f
1179 move.b #0,d1
11800:
80560599 1181 and.b #0xf8,d5
27d5cc88 1182 or.b d1,d5
318e20ff 1183 bra vbl_end
27d5cc88 1184
1185msm_no_ud:
1186 btst.l #4,d0 /* A - confirm */
1187 beq msm_no_a
1188 move.b d5,d1
80560599 1189 and.b #7,d1
27d5cc88 1190 bne 0f
1191 change_mode MMODE_GOTO, MMODE_MAIN
1192 bsr start_menu_box
318e20ff 1193 bra vbl_end
27d5cc88 11940:
1195 cmp.b #1,d1
1196 bne 0f
1197 moveq.l #0,d5
1198 change_mode MMODE_GOTO_PREDEF, MMODE_MAIN
1199 bsr start_menu_box
318e20ff 1200 bra vbl_end
27d5cc88 12010:
1202 cmp.b #2,d1
1203 bne 0f
d90ff128 1204 change_mode MMODE_JMP_ADDR, MMODE_MAIN
1205 bsr start_menu_box
318e20ff 1206 bra vbl_end
d90ff128 12070:
1208 cmp.b #3,d1
1209 bne 0f
8689c962 1210 change_mode MMODE_PC, MMODE_MAIN
80560599 1211 bsr start_menu_box
1212 bra vbl_end
12130:
1214 cmp.b #4,d1
1215 bne 0f
27d5cc88 1216 bchg.l #4,d6
318e20ff 1217 bra vbl_end
27d5cc88 12180:
1219
1220msm_no_a:
1221 move.w d0,d1
1222 and.w #0x3000,d1
1223 beq msm_no_bc
1224 bra return_to_main
1225
1226msm_no_bc:
318e20ff 1227 bra vbl_end
27d5cc88 1228
1229start_menu_box:
1230 movea.l #0xe000+10*2+8*64*2,a1
80560599 1231 move.w #11-1,d1
27d5cc88 12320:
1233 move.w a1,a0
1234 jsr load_prepare
1235 move.w #20-1,d0
12361:
1237 move.w #0,(a0)
1238 dbra d0,1b
1239
1240 add.w #64*2,a1
1241 dbra d1,0b
1242 rts
1243
1244################### goto predef ##################
1245
1246mode_goto_predef:
1247 /* frame */
1248 movea.l #0xe000+14*2+8*64*2,a1
1249 move.l #predef_addr_cnt+2-1,d1
12500:
1251 move.w a1,a0
1252 jsr load_prepare
1253 moveq.l #10-1,d0
12541:
1255 move.w #0,(a0)
1256 dbra d0,1b
1257
1258 add.w #64*2,a1
1259 dbra d1,0b
1260
1261 /* draw addresses */
1262 movea.l #0xe000+17*2+9*64*2,a1
318e20ff 1263 lea (predef_addrs,pc),a2
27d5cc88 1264 move.w #predef_addr_cnt-1,d4
1265 move.l #0x8006,d3
1266mgp_da_loop:
1267 move.w a1,a0
1268 jsr load_prepare
1269 move.l (a2)+,d2
1270 jsr print_hex_preped
1271 add.w #64*2,a1
1272 dbra d4,mgp_da_loop
1273
1274 /* cursor */
1275 movea.l #0xe000+15*2+9*64*2,a0
1276 moveq.l #0,d0
1277 move.b d5,d0
1278 lsl.w #7,d0
1279 add.w d0,a0
1280 jsr load_prepare
1281 move.w #'>',(a0)
1282
1283 /* input */
1284 jsr get_input /* x0cbrldu x1sa00du */
1285
1286 move.w d0,d1
1287 and.w #3,d1
1288 beq mgp_no_ud
1289 btst.l #0,d0
1290 sne d2
1291 or.b #1,d2 /* up -1, down 1 */
1292 add.b d2,d5
1293 cmp.b #0,d5
1294 bge 0f
1295 move.b #predef_addr_cnt-1,d5
12960:
1297 cmp.b #predef_addr_cnt-1,d5
1298 ble 0f
1299 move.b #0,d5
13000:
318e20ff 1301 bra vbl_end
27d5cc88 1302
1303mgp_no_ud:
1304 btst.l #4,d0 /* A - confirm */
1305 beq mgp_no_a
1306 moveq.l #0,d0
1307 move.b d5,d0
1308 lsl.w #2,d0
318e20ff 1309 lea (predef_addrs,pc),a0
27d5cc88 1310 move.l (a0,d0),d5
1311 lsl.l #8,d5
318e20ff 1312 bra mode_goto_finish
27d5cc88 1313
1314mgp_no_a:
1315 move.w d0,d1
1316 and.w #0x3000,d1
1317 beq mgp_no_bc
1318 bra return_to_main
1319
1320mgp_no_bc:
318e20ff 1321 bra vbl_end
27d5cc88 1322
d90ff128 1323##################### jmp ########################
1324
1325mode_jmp_addr:
1326 btst.l #7,d6
1327 bne mode_jmp_finish
1328
1329 moveq.l #0,d5
1330 or.b #3,d5 /* 3 bytes */
1331 bclr.l #7,d6
1332 change_mode MMODE_VAL_INPUT, MMODE_JMP_ADDR
318e20ff 1333 bra vbl_end
d90ff128 1334
1335mode_jmp_finish:
1336 lsr.l #8,d5
1337 write_vdp_r_dst 1,(VDP1_E_DISPLAY | VDP1_MODE5),(GFXCNTL) /* disable vint */
1338 move.l d5,a0
1339 jmp (a0)
1340
80560599 1341mode_transfer:
8689c962 1342 move.b #0x40,(0xa1000b).l /* port 2 ctrl */
1343 move.b #0x00,(0xa10005).l /* port 2 data - start with TH low */
80560599 1344
8689c962 1345 lea (txt_transfer_ready,pc),a0
80560599 1346 move.l #13,d0
1347 move.l #13,d1
1348 move.l #0x8000,d2
1349 jsr print
1350
1351wait_tl_low0:
1352 move.b (0xa10005),d0
1353 btst.b #4,d0
1354 bne wait_tl_low0
1355
1356 menu_text txt_working, 13, 13, 0
f0e06736 1357 bsr do_transfer
1358 bra return_to_main
27d5cc88 1359
4dfddc2f 1360# go back to main mode
1361return_to_main:
5f6473d9 1362 bclr.l #7,d6 /* not edited */
4dfddc2f 1363 change_mode MMODE_MAIN, MMODE_MAIN
27d5cc88 1364 write_vdp_r_dst 12,(VDP12_SCREEN_V224 | VDP12_SCREEN_H320),(GFXCNTL)
318e20ff 1365 bra vbl_end
fbad1b76 1366
1367
4db6e09f 1368#################################################
1369# #
1370# Initialize VDP registers #
1371# #
1372#################################################
1373
1374init_gfx:
1375 move.l #GFXCNTL,a3
570c4371 1376 write_vdp_reg 0,(VDP0_E_DISPLAY | VDP0_PLTT_FULL)
318e20ff 1377 write_vdp_reg 1,(VDP1_E_DISPLAY | VDP1_MODE5)
4db6e09f 1378 write_vdp_reg 2,(0xe000 >> 10) /* Screen map a adress */
1379 write_vdp_reg 3,(0xe000 >> 10) /* Window address */
1380 write_vdp_reg 4,(0xc000 >> 13) /* Screen map b address */
1381 write_vdp_reg 5,(0xfc00 >> 9) /* Sprite address */
1382 write_vdp_reg 6,0
570c4371 1383 write_vdp_reg 7,0 /* Backdrop color */
80560599 1384 write_vdp_reg 0x0a,1 /* Lines per hblank interrupt */
1385 write_vdp_reg 0x0b,0 /* 2-cell vertical scrolling */
1386 write_vdp_reg 0x0c,(VDP12_SCREEN_V224 | VDP12_SCREEN_H320)
1387 write_vdp_reg 0x0d,(0x8000 >> 10) /* Horizontal scroll address */
1388 write_vdp_reg 0x0e,0
1389 write_vdp_reg 0x0f,2
1390 write_vdp_reg 0x10,(VDP16_MAP_V32 | VDP16_MAP_H64) /* layer size */
1391 write_vdp_reg 0x11,0
1392 write_vdp_reg 0x12,0
4db6e09f 1393 rts
1394
1395
d4279640 1396# get mask of bits representing safe words
27d5cc88 1397# a1 - address to check
1398# destroys d0-d2, strips upper bits from a1
d4279640 1399get_safety_mask:
27d5cc88 1400 move.l a1,d1
1401 lsl.l #8,d1
1402 lsr.l #8,d1
318e20ff 1403 lea (safe_addrs,pc),a1
27d5cc88 1404 move.w #(safe_addrs_end - safe_addrs)/8-1,d2
14050:
1406 move.l (a1)+,d0
1407 cmp.l d0,d1
1408 blt 1f
1409 move.l (a1),d0
1410 cmp.l d0,d1
1411 ble addr_safe
14121:
1413 addq.l #4,a1
1414 dbra d2,0b
1415
27d5cc88 1416 move.l d1,a1
d4279640 1417
1418 moveq.l #0x0c,d0
1419 cmp.l #0xa14000,d1
1420 beq gsm_rts
1421
1422 moveq.l #0x08,d0
1423 cmp.l #0xa14100,d1
1424 beq gsm_rts
1425
1426 /* check for VDP address */
1427 move.l d1,d0
1428 swap d0
1429 and.b #0xe0,d0
1430 cmp.b #0xc0,d0
1431 bne addr_unsafe /* not vdp */
1432
1433 move.l d1,d0
1434 and.l #0x0700e0,d0
1435 bne addr_unsafe
1436
1437 move.l d1,d0
1438 and.b #0x1f,d0
1439 cmp.b #0x04,d0
1440 blt addr_hsafe_3 /* data port */
1441 cmp.b #0x10,d0
1442 blt addr_safe /* below PSG */
1443 cmp.b #0x18,d0
1444 bge addr_safe /* above PSG */
1445
1446addr_unsafe:
1447 moveq.l #0,d0 /* skip line */
1448 rts
1449
1450addr_hsafe_3:
1451 moveq.l #3,d0 /* skip 2 words */
27d5cc88 1452 rts
1453
1454addr_safe:
1455 move.l d1,a1
d4279640 1456 moveq.l #0xf,d0
1457gsm_rts:
27d5cc88 1458 rts
1459
1460
1286a1ba 1461# read single phase from controller
fbad1b76 1462# #a0 - addr
1286a1ba 1463# d0 - result
fbad1b76 1464# destroys d1,d2
1286a1ba 1465get_input:
1466 move.b #0x40,(0xa10003)
1467 nop
1468 nop
1469 nop
1470 move.b (0xa10003),d0
1471 move.b #0x00,(0xa10003)
1472 lsl.w #8,d0
1473 nop
1474 move.b (0xa10003),d0
1475 eor.w #0xffff,d0
fbad1b76 1476
1477 swap d7
1478 move.w d7,d1
1479 eor.w d0,d1 /* changed btns */
1480 move.w d0,d7 /* old val */
1481 swap d7
1482 and.w d0,d1 /* what changed now */
1483 bne 0f
1484
1485 addq.b #1,d6
1486 move.b d6,d2
27d5cc88 1487 and.b #0x0f,d2 /* do autorepeat */
1488 cmp.b #9,d2
fbad1b76 1489 bne 1f
1490 move.w d0,d1
14910:
27d5cc88 1492 and.b #0xf0,d6
fbad1b76 14931:
1494 swap d0
1495 move.w d1,d0
1286a1ba 1496 rts
1497
4dfddc2f 1498# Prepare to write to VDP RAM @a0
0fc4f06b 1499# sets a0 to VDP data port for convenience
1500# a0: VRAM base
1501# destroys d0
570c4371 1502
4db6e09f 1503load_prepare:
0fc4f06b 1504 VRAM_ADDR_var a0
1505 move.l d0,(GFXCNTL).l
1506 move.l #GFXDATA,a0
4db6e09f 1507 rts
1508
1509
0fc4f06b 1510# Load color data from ROM
1511# a0: CRAM base
1512# a1: color list address
1513# d0: number of colors to load
1514# destroys d1
4db6e09f 1515
1516load_colors:
0fc4f06b 1517 move.l d0,d1
1518 CRAM_ADDR_var a0
1519 move.l d0,(GFXCNTL).l
4db6e09f 1520
0fc4f06b 1521 move.l #GFXDATA,a0
1522 subq.w #1,d1
15230:
1524 move.w (a1)+,(a0)
1525 dbra d1,0b
4db6e09f 1526
1527 rts
1528
0fc4f06b 1529
1530# print
1531# a0 - string
1532# d0 - x
1533# d1 - y
4dfddc2f 1534# d2 - tile_bits[15:11]
0fc4f06b 1535# destroys a1
570c4371 1536
1537print:
0fc4f06b 1538 move.l a0,a1
1286a1ba 1539 XY2NT
0fc4f06b 1540 jsr load_prepare
4dfddc2f 1541 move.l d2,d0
1542 and.w #0xf800,d0
570c4371 1543
1544_print_loop:
0fc4f06b 1545 move.b (a1)+,d0
570c4371 1546 beq _print_end
1547
0fc4f06b 1548 move.w d0,(a0)
318e20ff 1549 bra _print_loop
570c4371 1550
1551_print_end:
1552 rts
1553
4db6e09f 1554
1286a1ba 1555# print_hex
1556# d0 - x
1557# d1 - y
1558# d2 - value
27d5cc88 1559# d3 - tile_bits[15:11]|digit_cnt[7:0]
4276cd7a 1560# destroys a0, preserves d3
1286a1ba 1561
1562print_hex:
1563 XY2NT
1564 jsr load_prepare
1565
1566print_hex_preped:
4276cd7a 1567 moveq.l #0,d0
1568 move.b d3,d0
1569 move.l d0,d1
1286a1ba 1570 lsl.b #2,d0
1571 ror.l d0,d2 /* prep value */
4276cd7a 1572 subq.l #1,d1 /* count */
1573 move.w d3,d0
1574 and.w #0xf800,d0 /* keep upper bits in d0 */
1286a1ba 1575
1576_print_hex_loop:
1577 rol.l #4,d2
1578 move.b d2,d0
1579 and.b #0xf,d0
1286a1ba 1580
1581 add.b #'0',d0
4276cd7a 1582 cmp.b #'9',d0
1583 ble 0f
1584 addq.b #7,d0
15850:
1286a1ba 1586 move.w d0,(a0)
4276cd7a 1587 dbra d1,_print_hex_loop
1286a1ba 1588
1589 rts
1590
1591
318e20ff 1592# wait vertical sync interrupt
4db6e09f 1593
1594wait_vsync:
fbad1b76 1595 move.b d7,d0
4db6e09f 1596_wait_change:
1597 stop #0x2000
fbad1b76 1598 cmp.b d7,d0
4db6e09f 1599 beq _wait_change
1600 rts
1601
1602
318e20ff 1603# wait vsync start (polling)
1604# destroys a0,d0
1605
1606wait_vsync_poll:
1607 move.l #GFXCNTL,a0
16080:
1609 move.w (a0),d0
1610 and.b #8,d0
1611 nop
1612 nop
1613 bne 0b
16140:
1615 move.w (a0),d0
1616 and.b #8,d0
1617 nop
1618 nop
1619 beq 0b
1620 rts
1621
1622
ff17c043 1623test_code:
ff17c043 1624 nop
ff17c043 1625
1626test_code_ret_op:
1627 jmp 0x123456 /* will be patched */
1628test_code_end:
1629
4db6e09f 1630#################################################
1631# #
1632# RAM DATA #
1633# #
1634#################################################
1635
1636.bss
570c4371 1637
fbad1b76 1638# nothing :)
4db6e09f 1639
1640.end
1641
1642# vim:filetype=asmM68k
Genesis/MegaDrive related projects