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

   1 //
   2 // Virtual 6808 Header file
   3 //
   4 // by James Hammons
   5 //
   6 // (C) 2006 Underground Software
   7 //
   8
   9 #ifndef __V6808_H__
  10 #define __V6808_H__
  11
  12 #include <stdint.h>
  13
  14 // Useful defines
  15
  16 #define FLAG_E          0x80            // ??? Entire ??? [No.]
  17 #define FLAG_F          0x40            // ??? Fast IRQ ??? [No.]
  18 #define FLAG_H          0x20            // Half carry
  19 #define FLAG_I          0x10            // IRQ
  20 #define FLAG_N          0x08            // Negative
  21 #define FLAG_Z          0x04            // Zero
  22 #define FLAG_V          0x02            // oVerflow
  23 #define FLAG_C          0x01            // Carry
  24
  25 #define V6808_ASSERT_LINE_RESET         0x0001          // v6808 RESET line
  26 #define V6808_ASSERT_LINE_IRQ           0x0002          // v6808 IRQ line
  27 #define V6808_ASSERT_LINE_NMI           0x0004          // v6808 NMI line
  28 #define V6808_STATE_WAI                         0x0008          // v6808 wait for IRQ line
  29 #define V6808_STATE_ILLEGAL_INST        0x0010          // Illegal instruction executed flag
  30 //#define V6809_START_DEBUG_LOG         0x0020          // Debug log go (temporary!)
  31
  32 // Useful structs
  33
  34 struct V6808REGS
  35 {
  36         uint16_t pc;                                    // 6808 PC register
  37         uint16_t x;                                             // 6808 X index register
  38         uint16_t s;                                             // 6808 System stack pointer
  39         uint8_t cc;                                             // 6808 Condition Code register
  40         uint8_t a;                                              // 6808 A register
  41         uint8_t b;                                              // 6808 B register
  42         uint64_t clock;                                 // 6808 clock
  43         uint8_t (* RdMem)(uint16_t);    // Address of uint8_t read routine
  44         void (* WrMem)(uint16_t, uint8_t);      // Address of uint8_t write routine
  45         uint32_t cpuFlags;                              // v6808 IRQ/RESET flags
  46         uint32_t clockOverrun;                  // Amount of overflow between runs
  47 };
  48
  49 // Function prototypes
  50
  51 void Execute6808(V6808REGS *, uint32_t);        // Function to execute 6808 instructions
  52 uint64_t GetCurrentV6808Clock(void);            // Get the clock of the currently executing CPU
  53 //uint8_t GetCCRegister(void);                          // Hmm.
  54
  55 #endif  // __V6808_H__
  56