Shamusworld >> Repos - stargem2/blob - src/v6808.h

   1 //
   2 // Virtual 6808 Header file
   3 //
   4 // by James Hammons
   5 //
   6 // (C) 2006 Underground Software
   7 //
   8 #ifndef __V6808_H__
   9 #define __V6808_H__
  10
  11 #include <stdint.h>
  12
  13 // Useful defines
  14
  15 #define FLAG_E          0x80            // ??? Entire ??? [No.]
  16 #define FLAG_F          0x40            // ??? Fast IRQ ??? [No.]
  17 #define FLAG_H          0x20            // Half carry
  18 #define FLAG_I          0x10            // IRQ
  19 #define FLAG_N          0x08            // Negative
  20 #define FLAG_Z          0x04            // Zero
  21 #define FLAG_V          0x02            // oVerflow
  22 #define FLAG_C          0x01            // Carry
  23
  24 #define V6808_LINE_RESET                        0x0001  // v6808 RESET line
  25 #define V6808_LINE_IRQ                          0x0002  // v6808 IRQ line
  26 #define V6808_LINE_NMI                          0x0004  // v6808 NMI line
  27 #define V6808_STATE_WAI                         0x0008  // v6808 wait for IRQ line
  28 #define V6808_STATE_ILLEGAL_INST        0x0010  // Illegal instruction executed flag
  29 //#define V6809_START_DEBUG_LOG         0x0020  // Debug log go (temporary!)
  30
  31 // Useful structs
  32
  33 struct V6808REGS
  34 {
  35         uint16_t pc;                                    // 6808 PC register
  36         uint16_t x;                                             // 6808 X index register
  37         uint16_t s;                                             // 6808 System stack pointer
  38         uint8_t cc;                                             // 6808 Condition Code register
  39         uint8_t a;                                              // 6808 A register
  40         uint8_t b;                                              // 6808 B register
  41         uint64_t clock;                                 // 6808 clock
  42         uint8_t (* RdMem)(uint16_t);    // Address of uint8 read routine
  43         void (* WrMem)(uint16_t, uint8_t);      // Address of uint8 write routine
  44         uint32_t cpuFlags;                              // v6808 IRQ/RESET flags
  45         uint32_t clockOverrun;                  // Amount of overflow between runs
  46 };
  47
  48 // Function prototypes
  49
  50 void Execute6808(V6808REGS *, uint32_t);        // Function to execute 6808 instructions
  51 uint64_t GetCurrentV6808Clock(void);            // Get the clock of the currently executing CPU
  52 //uint8 GetCCRegister(void);                            // Hmm.
  53
  54 #endif  // __V6808_H__
  55