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comparison transz80.c @ 250:5f1b68cecfc7

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Implemented basic interrupt support in Z80 core.
author Mike Pavone <pavone@retrodev.com>
date Mon, 29 Apr 2013 00:59:50 -0700
parents ea3899e3e7ec
children fd7c24b97ebf
comparison
equal deleted inserted replaced
249:d94e6cd5a8a5 250:5f1b68cecfc7
1 #include "z80inst.h" 1 #include "z80inst.h"
2 #include "z80_to_x86.h" 2 #include "z80_to_x86.h"
3 #include "mem.h" 3 #include "mem.h"
4 #include "vdp.h"
4 #include <stdio.h> 5 #include <stdio.h>
5 #include <stdlib.h> 6 #include <stdlib.h>
6 7
7 uint8_t z80_ram[0x2000]; 8 uint8_t z80_ram[0x2000];
8 uint16_t cart[0x200000]; 9 uint16_t cart[0x200000];
10
11 #define MCLKS_PER_Z80 15
12 //TODO: Figure out the exact value for this
13 #define MCLKS_PER_FRAME (MCLKS_LINE*262)
14 #define VINT_CYCLE ((MCLKS_LINE * 226)/MCLKS_PER_Z80)
15 #define CYCLE_NEVER 0xFFFFFFFF
9 16
10 int main(int argc, char ** argv) 17 int main(int argc, char ** argv)
11 { 18 {
12 long filesize; 19 long filesize;
13 uint8_t *filebuf; 20 uint8_t *filebuf;
36 fseek(f, 0, SEEK_END); 43 fseek(f, 0, SEEK_END);
37 filesize = ftell(f); 44 filesize = ftell(f);
38 fseek(f, 0, SEEK_SET); 45 fseek(f, 0, SEEK_SET);
39 fread(cart, 1, filesize < sizeof(cart) ? filesize : sizeof(cart), f); 46 fread(cart, 1, filesize < sizeof(cart) ? filesize : sizeof(cart), f);
40 fclose(f); 47 fclose(f);
48 for(unsigned short * cur = cart; cur - cart < (filesize/2); ++cur)
49 {
50 *cur = (*cur >> 8) | (*cur << 8);
51 }
41 } 52 }
42 init_x86_z80_opts(&opts); 53 init_x86_z80_opts(&opts);
43 init_z80_context(&context, &opts); 54 init_z80_context(&context, &opts);
44 //Z80 RAM 55 //Z80 RAM
45 context.mem_pointers[0] = z80_ram; 56 context.mem_pointers[0] = z80_ram;
46 context.sync_cycle = context.target_cycle = 0x7FFFFFFF; 57 context.sync_cycle = context.target_cycle = MCLKS_PER_FRAME/MCLKS_PER_Z80;
58 context.int_cycle = CYCLE_NEVER;
47 //cartridge/bank 59 //cartridge/bank
48 context.mem_pointers[1] = context.mem_pointers[2] = cart; 60 context.mem_pointers[1] = context.mem_pointers[2] = (uint8_t *)cart;
49 z80_reset(&context); 61 z80_reset(&context);
50 for(;;) 62 for(;;)
51 { 63 {
52 z80_run(&context); 64 z80_run(&context);
65 if (context.current_cycle >= MCLKS_PER_FRAME/MCLKS_PER_Z80) {
66 context.current_cycle -= MCLKS_PER_FRAME/MCLKS_PER_Z80;
67 }
68 if (context.current_cycle < VINT_CYCLE && context.iff1) {
69 context.int_cycle = VINT_CYCLE;
70 }
71 context.target_cycle = context.sync_cycle < context.int_cycle ? context.sync_cycle : context.int_cycle;
53 } 72 }
54 return 0; 73 return 0;
55 } 74 }