src/state.h

Thu, 02 Dec 2010 17:01:34 +0000

author
Philip Pemberton <philpem@philpem.me.uk>
date
Thu, 02 Dec 2010 17:01:34 +0000
changeset 32
a44afcf2354c
parent 26
fef12817c5e8
child 37
87662afa1d98
permissions
-rw-r--r--

Implement memory mapping and access checking

philpem@18 1 #ifndef _STATE_H
philpem@18 2 #define _STATE_H
philpem@18 3
philpem@18 4 #include <stddef.h>
philpem@18 5 #include <stdint.h>
philpem@18 6 #include <stdbool.h>
philpem@18 7
philpem@18 8 // Maximum size of the Boot PROMs. Must be a binary power of two.
philpem@18 9 #define ROM_SIZE 32768
philpem@18 10
philpem@18 11 /**
philpem@18 12 * @brief Emulator state storage
philpem@18 13 *
philpem@18 14 * This structure stores the internal state of the emulator.
philpem@18 15 */
philpem@18 16 typedef struct {
philpem@18 17 // Boot PROM can be up to 32Kbytes total size
philpem@18 18 uint8_t rom[ROM_SIZE]; ///< Boot PROM data buffer
philpem@18 19
philpem@18 20 // Main system RAM
philpem@18 21 uint8_t *ram; ///< RAM data buffer
philpem@18 22 size_t ram_size; ///< Size of RAM buffer in bytes
philpem@18 23
philpem@24 24 // Video RAM
philpem@24 25 uint8_t vram[0x8000]; ///< Video RAM
philpem@24 26
philpem@26 27 // Map RAM
philpem@26 28 uint8_t map[0x800]; ///< Map RAM
philpem@26 29
philpem@32 30 // General Status Register
philpem@32 31 uint16_t genstat;
philpem@32 32
philpem@18 33 // GENERAL CONTROL REGISTER
philpem@18 34 /// GENCON.ROMLMAP -- false ORs the address with 0x800000, forcing the
philpem@18 35 /// 68010 to access ROM instead of RAM when booting. TRM page 2-36.
philpem@24 36 bool romlmap;
philpem@18 37 } S_state;
philpem@18 38
philpem@18 39 // Global emulator state. Yes, I know global variables are evil, please don't
philpem@18 40 // email me and lecture me about it. -philpem
philpem@18 41 #ifndef _STATE_C
philpem@18 42 extern S_state state;
philpem@18 43 #else
philpem@18 44 S_state state;
philpem@18 45 #endif
philpem@18 46
philpem@18 47 /**
philpem@18 48 * @brief Initialise system state
philpem@18 49 *
philpem@18 50 * @param ramsize RAM size in bytes -- must be a multiple of 512KiB, min 512KiB, max 4MiB.
philpem@18 51 *
philpem@18 52 * Initialises the emulator's internal state.
philpem@18 53 */
philpem@18 54 int state_init(size_t ramsize);
philpem@18 55
philpem@18 56 /**
philpem@18 57 * @brief Deinitialise system state
philpem@18 58 *
philpem@18 59 * Deinitialises the saved state, and frees all memory. Call this function
philpem@18 60 * before exiting your program to avoid memory leaks.
philpem@18 61 */
philpem@18 62 void state_done();
philpem@18 63
philpem@18 64 #endif