3 * (C) 2018 by Andreas Eversberg <jolly@eversberg.eu>
6 * This program is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 3 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
23 #include "../libcpu/m68k.h"
24 #include "mercenary.h"
26 #define INITIAL_STACK 0x7fffa
27 #define RESET_VECTOR 0x59484
28 const uint32_t mercenary_stop_at[] = {
29 0x59a4e, /* done with rendering, waiting for VBL */
30 0x54c26, /* after pressing 'HELP' key before showing menu line on benson */
31 0x55438, /* waiting for menu command */
32 0x54c2e, /* after pressing 'HELP' key while showing menu line on benson */
33 0x55446, /* after pressing 'RETURN' while game waits for other key to resume */
34 0x51620, /* after dying, waiting for VBL to fade out palette */
36 }; /* break points for rendering and continue with processing loop */
38 extern const uint32_t mercenary2_hex[];
39 extern int mercenary2_hex_size;
41 void mercenary_load(void)
45 /* load game binary from constant to volatile memory */
46 for (i = 0; i < mercenary2_hex_size; i += 4) {
47 m68k_write_memory_32(i, mercenary2_hex[i / 4]);
51 void mercenary_patch(void)
54 m68k_write_memory_32(0x00000, INITIAL_STACK);
57 m68k_write_memory_32(0x00004, RESET_VECTOR);
59 /* remove wait for VBL */
60 m68k_write_memory_16(0x59a54, 0x4e71); /* nop */
62 /* reduce loop that waits for disk stepper to move */
63 if (m68k_read_memory_32(0x55398) != 0x0000091b) {
64 fprintf(stderr, "expecting loop counter of 0x0000091b here, please fix!\n");
67 m68k_write_memory_32(0x55398, 1);
68 /* reduce loop that waits for disk side change */
69 if (m68k_read_memory_32(0x54ffc) != 0x00000d02) {
70 fprintf(stderr, "expecting loop counter of 0x00000d02 here, please fix!\n");
73 m68k_write_memory_32(0x54ffc, 1);
76 uint32_t mercenary_palette(void)
78 return m68k_read_memory_32(0x007c14);