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lc3.h
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lc3.h
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/**
* LC-3 Simulator
* Final Project (Project #6)
* TCSS 372 - Computer Architecture
* Spring 2018
*
* LC-3 Module Header File
*
* This is a simulator of the LC-3 (Little Computer) machine using an
* object-oriented approach in C. The simulator includes all standard LC-3
* functionality based on the finite state machine approach and the corresponding
* opcode tables for the machine, with an additional push-pop stack feature utilized
* on the previously reserved (1101) opcode.
*
* Group Members:
* Michael Fulton
* Enoch Chan
* Logan Stafford
*
* Base Code Contributors:
* Sam Brendel
* Michael Josten
* Sam Anderson
* Tyler Schupack
*/
#ifndef LC3_H
#define LC3_H
#include "global.h"
#include "alu.h"
#include "cpu.h"
#include "memory.h"
/** FSM microstates */
#define STATE_FETCH 0
#define STATE_DECODE 1
#define STATE_EVAL_ADDR 2
#define STATE_FETCH_OP 3
#define STATE_EXECUTE 4
#define STATE_STORE 5
/** Instruction opcodes */
#define OPCODE_ADD 1 /* 0001 */
#define OPCODE_AND 5 /* 0101 */
#define OPCODE_NOT 9 /* 1001 */
#define OPCODE_BR 0 /* 0000 */
#define OPCODE_JMP 12 /* 1100 */
#define OPCODE_RET 12 /* 1100 */
#define OPCODE_JSR 4 /* 0100 */
#define OPCODE_TRAP 15 /* 1111 */
#define OPCODE_LD 2 /* 0010 */
#define OPCODE_LDI 10 /* 1010 */
#define OPCODE_LDR 6 /* 0110 */
#define OPCODE_LEA 14 /* 1101 */
#define OPCODE_ST 3 /* 0011 */
#define OPCODE_STI 11 /* 1011 */
#define OPCODE_STR 7 /* 0111 */
#define OPCODE_STACK 13 /* 1101 */
/** Stack status codes. Used for the LC-3 stack push/pop opcode */
#define STACK_MAX 0x31F6
#define STACK_BASE 0x31FF
#define STACK_LAST 0x31FE
#define STACK_PUSH 0
#define STACK_POP 1
#define STACK_SUCCESS 1
#define STACK_ERROR 0
/** Mask used to isolating various bits */
#define BIT_IMMED5 16 /* 0000 0000 0001 0000 */
#define BIT_PCOFFSET11 1024 /* 0000 0100 0000 0000 */
#define BIT_PCOFFSET9 256 /* 0000 0001 0000 0000 */
#define BIT_PCOFFSET6 32 /* 0000 0000 0010 0000 */
/** How many times to shift the bits to isolated various values in the IR */
#define BITSHIFT_OPCODE 12
#define BITSHIFT_DR 9
#define BITSHIFT_NZP 9
#define BITSHIFT_SR1 6
#define BITSHIFT_BIT5 5
#define BITSHIFT_BIT11 11
#define BITSHIFT_NEGATIVE_IMMED5 4
#define BITSHIFT_NEGATIVE_PCOFFSET11 10
#define BITSHIFT_NEGATIVE_PCOFFSET9 8
#define BITSHIFT_NEGATIVE_PCOFFSET6 5
#define MASK_OPCODE 61440 // 1111 0000 0000 0000
#define MASK_DR 3584 // 0000 1110 0000 0000
#define MASK_SR1 448 // 0000 0001 1100 0000
#define MASK_SR2 7 // 0000 0000 0000 0111
#define MASK_PCOFFSET11 2047 // 0000 0111 1111 1111
#define MASK_PCOFFSET9 511 // 0000 0001 1111 1111
#define MASK_PCOFFSET6 63 // 0000 0000 0011 1111
#define MASK_TRAPVECT8 255 // 0000 0000 1111 1111
#define MASK_BIT11 2048 // 0000 1000 0000 0000
#define MASK_BIT5 32 // 0000 0000 0010 0000
#define MASK_IMMED5 31 // 0000 0000 0001 1111
#define MASK_NZP 3584 // 0000 1110 0000 0000
#define MASK_NEGATIVE_IMMED5 0xFFE0 // 1111 1111 1110 0000
#define MASK_NEGATIVE_PCOFFSET11 0xF800 // 1111 1000 0000 0000
#define MASK_NEGATIVE_PCOFFSET9 0xFE00 // 1111 1110 0000 0000
#define MASK_NEGATIVE_PCOFFSET6 0xFFC0 // 1111 1111 1100 0000
typedef struct lc3_t {
cpu_p cpu;
alu_p alu;
memory_p memory;
word_t starting_address;
bool_t is_halted;
bool_t is_file_loaded;
/** Intra-state variables */
state_t state;
opcode_t opcode;
word_t eval_addr_calculation;
bool_t branch_enabled;
trap_vector_t trap_vector;
} lc3_t, *lc3_p;
/** Allocates and initializes a new LC3 module */
lc3_p lc3_create();
/** Reinitializes the LC3 module without reallocation */
void lc3_reset(lc3_p);
/** Deallocates the LC3 module */
void lc3_destroy(lc3_p);
/** Gets a snapshot of the LC3 data for debugging or display purposes */
const lc3_snapshot_t lc3_get_snapshot(lc3_p);
/** Gets/sets the starting address for the PC according to the first line in the loaded hex
* file */
word_t lc3_get_starting_address(lc3_p);
void lc3_set_starting_address(lc3_p, word_t);
/** Checks/toggles whether the LC3 is halted */
bool_t lc3_is_halted(lc3_p lc3);
void lc3_toggle_halted(lc3_p lc3);
/** Checks/toggles whether the LC3 has a file loaded */
bool_t lc3_has_file_loaded(lc3_p);
void lc3_toggle_file_loaded(lc3_p);
/** Gets/sets the current microstate of the LC3 */
state_t lc3_get_state(lc3_p);
void lc3_set_state(lc3_p, state_t);
/** Gets the opcode currently being processed */
opcode_t lc3_get_opcode(lc3_p);
/** Gets the current PC. This is needed for the Display/debugger to check if the user is
* requesting a breakpoint at this location */
word_t lc3_get_pc(lc3_p);
/** Sets memory data at the specified address. This is used for loading a file to memory and
* editing memory from the Display */
void lc3_set_memory(lc3_p, word_t address, word_t data);
/** Fetch instruction cycle */
void lc3_fetch(lc3_p);
/** Decode instruction cycle */
void lc3_decode(lc3_p);
/** The remaining instruction cycles are grouped by operation */
/** ADD */
void lc3_fetch_op_add(lc3_p);
void lc3_execute_add(lc3_p);
void lc3_store_add(lc3_p);
/** AND */
void lc3_fetch_op_and(lc3_p);
void lc3_execute_and(lc3_p);
void lc3_store_and(lc3_p);
/** BR */
void lc3_eval_addr_br(lc3_p);
void lc3_execute_br(lc3_p);
/** JMP */
void lc3_eval_addr_jmp(lc3_p);
void lc3_store_jmp(lc3_p);
/** JSR */
void lc3_eval_addr_jsr(lc3_p);
void lc3_store_jsr(lc3_p);
/** LD */
void lc3_eval_addr_ld(lc3_p);
void lc3_fetch_op_ld(lc3_p);
void lc3_store_ld(lc3_p);
/** LDI */
void lc3_eval_addr_ldi(lc3_p);
void lc3_fetch_op_ldi(lc3_p);
void lc3_store_ldi(lc3_p);
/** LDR */
void lc3_eval_addr_ldr(lc3_p);
void lc3_fetch_op_ldr(lc3_p);
void lc3_store_ldr(lc3_p);
/** LEA */
void lc3_eval_addr_lea(lc3_p);
void lc3_store_lea(lc3_p);
/** NOT */
void lc3_fetch_op_not(lc3_p);
void lc3_execute_not(lc3_p);
void lc3_store_not(lc3_p);
/** ST */
void lc3_eval_addr_st(lc3_p);
void lc3_fetch_op_st(lc3_p);
void lc3_store_st(lc3_p);
/** STI */
void lc3_eval_addr_sti(lc3_p);
void lc3_fetch_op_sti(lc3_p);
void lc3_store_sti(lc3_p);
/** STR */
void lc3_eval_addr_str(lc3_p);
void lc3_fetch_op_str(lc3_p);
void lc3_store_str(lc3_p);
/** Stack */
void lc3_fetch_op_stack(lc3_p);
void lc3_store_stack(lc3_p);
/** TRAP */
void lc3_fetch_op_trap(lc3_p);
word_t lc3_execute_trap(lc3_p);
/** LC3 portion of the GETC routine */
void lc3_trap_x20(lc3_p, char);
/** LC3 portion of the OUT routine */
char lc3_trap_x21(lc3_p);
/** LC3 portion of the PUTS routine */
char lc3_trap_x22(lc3_p);
/** LC3 HALT routine */
void lc3_trap_x25(lc3_p);
#endif