63 lines
973 B
C
63 lines
973 B
C
#ifndef CPU_H
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#define CPU_H
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#define MEM_SIZE 256
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#define NUM_REGISTERS 8
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#define BUF_MAX 256
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/*
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* Instruction set
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* Here, we're making a RISC (reduced instruction set computer)
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* so we're staying minimalistic.
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*/
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typedef enum
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{
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// 0x00 -> No operation
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NOP = 0,
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// 0xA? -> Memory operations
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MOV = 0xA0,
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PUT = 0xA1,
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// 0xB? -> Arithmetic operations
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ADD = 0xB0,
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SUB = 0xB1,
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MUL = 0xB2,
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DIV = 0xB3,
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// 0xC? -> Bitwise operations
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OR = 0xC0,
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AND = 0xC1,
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XOR = 0xC2,
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// 0xD? -> Input/output operations
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OUT = 0xD0,
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IN = 0xD1,
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// 0xE? -> Jump and comparisons
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JMP = 0xE0,
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JEQ = 0xE1,
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CMP = 0xE2,
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// 0xF? -> Misc operations
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HLT = 0xFF
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} instruction_set_t;
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/*
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* CPU structure definition
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* Contains 4 8-bit registers, memory, a program counter, a halt switch, and flags.
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*/
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typedef struct
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{
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uint8_t reg[NUM_REGISTERS];
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uint8_t memory[MEM_SIZE];
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uint16_t pc;
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bool halted;
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bool equal_flag;
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int flag_clear_delay;
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} CPU_t;
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#endif
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