diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..af22c9d
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,23 @@
+.idea/
+.vscode/
+
+*.class
+
+.guides/secure/grading-config/*.cfg
+.guides/secure/test-libs/*
+
+.guides/secure/test-cases/**/*.java
+.guides/secure/user-libs/*.jar
+.guides/secure/user-submissions/*.java
+*.txt
+
+libs/*.jar
+submit/*.java
+tests/*
+!tests/.gitkeep
+
+TEST-junit-*.xml
+
+*.o
+assembler
+*.obj
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..8e37ca2
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,27 @@
+CC = gcc  
+CFLAGS = -Wall -Wextra -I.  
+SRC_ASSEMBLER = assembler.c  
+SRC_ASM_PARSER = asm_parser.c  
+OBJ_ASM_PARSER = asm_parser.o  
+TARGET = assembler  
+all: $(TARGET)
+
+assembler: $(OBJ_ASM_PARSER) $(SRC_ASSEMBLER)  
+	$(CC) $(CFLAGS) -o $(TARGET) $(OBJ_ASM_PARSER) $(SRC_ASSEMBLER)  
+
+asm_parser.o: $(SRC_ASM_PARSER)  
+	$(CC) $(CFLAGS) -c $(SRC_ASM_PARSER)
+
+clean:  
+	rm -f $(OBJ_ASM_PARSER)
+
+clobber: clean  
+	rm -f $(TARGET)  
+	rm -f *~  
+	rm -f *.bak  
+	rm -f *.tmp  
+	rm -f *.o  
+	rm -f core
+
+# Phony targets  
+.PHONY: all clean clobber
\ No newline at end of file
diff --git a/asm_parser.c b/asm_parser.c
index 8c7d174..e7de8ec 100644
--- a/asm_parser.c
+++ b/asm_parser.c
@@ -14,4 +14,337 @@
 #include <stdlib.h>
 #include "asm_parser.h"
 
+int read_asm_file(char *filename, char program[ROWS][COLS]) {
+  FILE *file = fopen(filename, "r");
+  if (!file) {
+    printf("Error opening file %s\n", filename);
+    return -1;
+  }
+  int line_num = 0;
+  while (fgets(program[line_num], COLS, file) != NULL && line_num < ROWS) {
+    // Remove trailing newline
+    size_t len = strlen(program[line_num]);
+    if (len > 0 && program[line_num][len - 1] == '\n') {
+      program[line_num][len - 1] = '\0';
+      len--;
+    }
+    // Remove comments starting with ';' or '#'
+    char *comment = strchr(program[line_num], ';');
+    if (comment != NULL) {
+      *comment = '\0';
+      len = comment - program[line_num];
+    }
+    comment = strchr(program[line_num], '#');
+    if (comment != NULL) {
+      *comment = '\0';
+      len = comment - program[line_num];
+    }
+    // Trim trailing whitespace
+    while (len > 0 && isspace(program[line_num][len - 1])) {
+      program[line_num][--len] = '\0';
+    }
+    // Skip empty lines
+    if (len == 0) {
+      continue;
+    }
+    line_num++;
+  }
+  fclose(file);
+  return line_num;
+}
+
+int parse_instruction(char *instr, char *instr_bin_str) {
+  // Remove leading whitespace
+  while (isspace(*instr)) instr++;
+  if (*instr == '\0') {
+    // Empty line
+    return 0;
+  }
+  // Tokenize the instruction
+  char instr_copy[COLS];
+  strcpy(instr_copy, instr);
+  char *token = strtok(instr_copy, " ,\t");
+  if (token == NULL) {
+    // Empty or invalid instruction
+    return -1;
+  }
+  to_uppercase(token);
+  if (strcmp(token, "ADD") == 0) {
+    return parse_add(instr, instr_bin_str);
+  } else if (strcmp(token, "MUL") == 0) {
+    return parse_mul(instr, instr_bin_str);
+  } else if (strcmp(token, "SUB") == 0) {
+    return parse_sub(instr, instr_bin_str);
+  } else if (strcmp(token, "DIV") == 0) {
+    return parse_div(instr, instr_bin_str);
+  } else if (strcmp(token, "AND") == 0) {
+    return parse_and(instr, instr_bin_str);
+  } else if (strcmp(token, "OR") == 0) {
+    return parse_or(instr, instr_bin_str);
+  } else if (strcmp(token, "XOR") == 0) {
+    return parse_xor(instr, instr_bin_str);
+  }
+  // Add other instructions here
+  else {
+    printf("Unknown instruction: %s\n", token);
+    return -1;
+  }
+}
+
+int parse_reg(char *reg_str) {
+  if (reg_str[0] != 'R' && reg_str[0] != 'r') {
+    printf("Invalid register: %s\n", reg_str);
+    return -1;
+  }
+  int reg_num = atoi(&reg_str[1]);
+  if (reg_num < 0 || reg_num > 7) {
+    printf("Invalid register number: %d\n", reg_num);
+    return -1;
+  }
+  return reg_num;
+}
+
+void int_to_bin_str(int num, int bits, char *bin_str) {
+  bin_str[bits] = '\0';
+  for (int i = bits - 1; i >= 0; i--) {
+    bin_str[i] = (num % 2) + '0';
+    num /= 2;
+  }
+}
+
+void to_uppercase(char *str) {
+  for (; *str; ++str) {
+    *str = toupper(*str);
+  }
+}
+
+int parse_add(char *instr, char *instr_bin_str) {
+  // Instruction format: ADD Rd, Rs, Rt
+  // Opcode: 0001
+  char opcode[] = "0001";
+  char ddd[4], sss[4], ttt[4];
+  // Tokenize the instruction to get registers
+  char instr_copy[COLS];
+  strcpy(instr_copy, instr);
+  char *token = strtok(instr_copy, " ,\t");  // Skip 'ADD'
+  token = strtok(NULL, " ,\t");  // Rd
+  if (token == NULL) return -1;
+  int rd = parse_reg(token);
+  token = strtok(NULL, " ,\t");  // Rs
+  if (token == NULL) return -1;
+  int rs = parse_reg(token);
+  token = strtok(NULL, " ,\t");  // Rt
+  if (token == NULL) return -1;
+  int rt = parse_reg(token);
+  if (rd < 0 || rs < 0 || rt < 0) return -1;
+  // Convert rd, rs, rt to 3-bit binary strings
+  int_to_bin_str(rd, 3, ddd);
+  int_to_bin_str(rs, 3, sss);
+  int_to_bin_str(rt, 3, ttt);
+  // Build the binary instruction string
+  sprintf(instr_bin_str, "%s%s%s000%s", opcode, ddd, sss, ttt);
+  return 1;
+}
+
+int parse_mul(char *instr, char *instr_bin_str) {
+  // Instruction format: MUL Rd, Rs, Rt
+  // Opcode: 0001
+  char opcode[] = "0001";
+  char ddd[4], sss[4], ttt[4];
+  // Tokenize the instruction to get registers
+  char instr_copy[COLS];
+  strcpy(instr_copy, instr);
+  char *token = strtok(instr_copy, " ,\t");  // Skip 'MUL'
+  token = strtok(NULL, " ,\t");  // Rd
+  if (token == NULL) return -1;
+  int rd = parse_reg(token);
+  token = strtok(NULL, " ,\t");  // Rs
+  if (token == NULL) return -1;
+  int rs = parse_reg(token);
+  token = strtok(NULL, " ,\t");  // Rt
+  if (token == NULL) return -1;
+  int rt = parse_reg(token);
+  if (rd < 0 || rs < 0 || rt < 0) return -1;
+  // Convert rd, rs, rt to 3-bit binary strings
+  int_to_bin_str(rd, 3, ddd);
+  int_to_bin_str(rs, 3, sss);
+  int_to_bin_str(rt, 3, ttt);
+  // Build the binary instruction string
+  sprintf(instr_bin_str, "%s%s%s001%s", opcode, ddd, sss, ttt);
+  return 1;
+}
+
+int parse_sub(char *instr, char *instr_bin_str) {
+  // Instruction format: SUB Rd, Rs, Rt
+  // Opcode: 0001
+  char opcode[] = "0001";
+  char ddd[4], sss[4], ttt[4];
+  // Tokenize the instruction to get registers
+  char instr_copy[COLS];
+  strcpy(instr_copy, instr);
+  char *token = strtok(instr_copy, " ,\t");  // Skip 'SUB'
+  token = strtok(NULL, " ,\t");  // Rd
+  if (token == NULL) return -1;
+  int rd = parse_reg(token);
+  token = strtok(NULL, " ,\t");  // Rs
+  if (token == NULL) return -1;
+  int rs = parse_reg(token);
+  token = strtok(NULL, " ,\t");  // Rt
+  if (token == NULL) return -1;
+  int rt = parse_reg(token);
+  if (rd < 0 || rs < 0 || rt < 0) return -1;
+  // Convert rd, rs, rt to 3-bit binary strings
+  int_to_bin_str(rd, 3, ddd);
+  int_to_bin_str(rs, 3, sss);
+  int_to_bin_str(rt, 3, ttt);
+  // Build the binary instruction string
+  sprintf(instr_bin_str, "%s%s%s010%s", opcode, ddd, sss, ttt);
+  return 1;
+}
+
+int parse_div(char *instr, char *instr_bin_str) {
+  // Instruction format: DIV Rd, Rs, Rt
+  // Opcode: 0001
+  char opcode[] = "0001";
+  char ddd[4], sss[4], ttt[4];
+  // Tokenize the instruction to get registers
+  char instr_copy[COLS];
+  strcpy(instr_copy, instr);
+  char *token = strtok(instr_copy, " ,\t");  // Skip 'DIV'
+  token = strtok(NULL, " ,\t");  // Rd
+  if (token == NULL) return -1;
+  int rd = parse_reg(token);
+  token = strtok(NULL, " ,\t");  // Rs
+  if (token == NULL) return -1;
+  int rs = parse_reg(token);
+  token = strtok(NULL, " ,\t");  // Rt
+  if (token == NULL) return -1;
+  int rt = parse_reg(token);
+  if (rd < 0 || rs < 0 || rt < 0) return -1;
+  // Convert rd, rs, rt to 3-bit binary strings
+  int_to_bin_str(rd, 3, ddd);
+  int_to_bin_str(rs, 3, sss);
+  int_to_bin_str(rt, 3, ttt);
+  // Build the binary instruction string
+  sprintf(instr_bin_str, "%s%s%s011%s", opcode, ddd, sss, ttt);
+  return 1;
+}
+
+int parse_and(char *instr, char *instr_bin_str) {
+  // Instruction format: AND Rd, Rs, Rt
+  // Opcode: 0101
+  char opcode[] = "0101";
+  char ddd[4], sss[4], ttt[4];
+  // Tokenize the instruction to get registers
+  char instr_copy[COLS];
+  strcpy(instr_copy, instr);
+  char *token = strtok(instr_copy, " ,\t");  // Skip 'AND'
+  token = strtok(NULL, " ,\t");  // Rd
+  if (token == NULL) return -1;
+  int rd = parse_reg(token);
+  token = strtok(NULL, " ,\t");  // Rs
+  if (token == NULL) return -1;
+  int rs = parse_reg(token);
+  token = strtok(NULL, " ,\t");  // Rt
+  if (token == NULL) return -1;
+  int rt = parse_reg(token);
+  if (rd < 0 || rs < 0 || rt < 0) return -1;
+  // Convert rd, rs, rt to 3-bit binary strings
+  int_to_bin_str(rd, 3, ddd);
+  int_to_bin_str(rs, 3, sss);
+  int_to_bin_str(rt, 3, ttt);
+  // Build the binary instruction string
+  sprintf(instr_bin_str, "%s%s%s000%s", opcode, ddd, sss, ttt);
+  return 1;
+}
+
+int parse_or(char *instr, char *instr_bin_str) {
+  // Instruction format: OR Rd, Rs, Rt
+  // Opcode: 0101
+  char opcode[] = "0101";
+  char ddd[4], sss[4], ttt[4];
+  // Tokenize the instruction to get registers
+  char instr_copy[COLS];
+  strcpy(instr_copy, instr);
+  char *token = strtok(instr_copy, " ,\t");  // Skip 'OR'
+  token = strtok(NULL, " ,\t");  // Rd
+  if (token == NULL) return -1;
+  int rd = parse_reg(token);
+  token = strtok(NULL, " ,\t");  // Rs
+  if (token == NULL) return -1;
+  int rs = parse_reg(token);
+  token = strtok(NULL, " ,\t");  // Rt
+  if (token == NULL) return -1;
+  int rt = parse_reg(token);
+  if (rd < 0 || rs < 0 || rt < 0) return -1;
+  // Convert rd, rs, rt to 3-bit binary strings
+  int_to_bin_str(rd, 3, ddd);
+  int_to_bin_str(rs, 3, sss);
+  int_to_bin_str(rt, 3, ttt);
+  // Build the binary instruction string
+  sprintf(instr_bin_str, "%s%s%s010%s", opcode, ddd, sss, ttt);
+  return 1;
+}
+
+int parse_xor(char *instr, char *instr_bin_str) {
+  // Instruction format: XOR Rd, Rs, Rt
+  // Opcode: 0101
+  char opcode[] = "0101";
+  char ddd[4], sss[4], ttt[4];
+  // Tokenize the instruction to get registers
+  char instr_copy[COLS];
+  strcpy(instr_copy, instr);
+  char *token = strtok(instr_copy, " ,\t");  // Skip 'XOR'
+  token = strtok(NULL, " ,\t");  // Rd
+  if (token == NULL) return -1;
+  int rd = parse_reg(token);
+  token = strtok(NULL, " ,\t");  // Rs
+  if (token == NULL) return -1;
+  int rs = parse_reg(token);
+  token = strtok(NULL, " ,\t");  // Rt
+  if (token == NULL) return -1;
+  int rt = parse_reg(token);
+  if (rd < 0 || rs < 0 || rt < 0) return -1;
+  // Convert rd, rs, rt to 3-bit binary strings
+  int_to_bin_str(rd, 3, ddd);
+  int_to_bin_str(rs, 3, sss);
+  int_to_bin_str(rt, 3, ttt);
+  // Build the binary instruction string
+  sprintf(instr_bin_str, "%s%s%s011%s", opcode, ddd, sss, ttt);
+  return 1;
+}
+
+unsigned short int str_to_bin(char *instr_bin_str) {
+  unsigned short int result = 0;
+  for (int i = 0; i < 16; i++) {
+    result <<= 1;
+    if (instr_bin_str[i] == '1') {
+      result |= 1;
+    } else if (instr_bin_str[i] != '0') {
+      // Invalid character
+      printf("Invalid binary string: %s\n", instr_bin_str);
+      return 0;
+    }
+  }
+  return result;
+}
+
+int write_obj_file(char *filename, unsigned short int program_bin[ROWS], int instr_count) {
+  FILE *file = fopen(filename, "wb");
+  if (!file) {
+    printf("Error opening file %s for writing\n", filename);
+    return -1;
+  }
+  // Write the code header: xCADE, address (start at 0), n (instr_count)
+  unsigned short int header[3];
+  header[0] = 0xCADE;
+  header[1] = 0x0000;  // Starting address, assume 0 for now
+  header[2] = instr_count;
+  fwrite(header, sizeof(unsigned short int), 3, file);
+  // Write the instructions
+  fwrite(program_bin, sizeof(unsigned short int), instr_count, file);
+  fclose(file);
+  return 0;
+}
+
 /* to do - implement all the functions in asm_parser.h */
\ No newline at end of file
diff --git a/asm_parser.h b/asm_parser.h
index e1eba35..800da29 100644
--- a/asm_parser.h
+++ b/asm_parser.h
@@ -9,14 +9,28 @@
  *
  */
 
+#ifndef ASM_PARSER_H
+#define ASM_PARSER_H
+
+#include <ctype.h>
+
 #define ROWS 100
 #define COLS 255
 
-int read_asm_file 		(char* filename, char program [ROWS][COLS] ) ;
-int parse_instruction 	(char* instr, char* instr_bin_str) ;
-int parse_reg 			(char reg_num, char* instr_bin_str) ;
-int parse_add 			(char* instr, char* instr_bin_str ) ;
-int parse_mul 			(char* instr, char* instr_bin_str ) ;
+int read_asm_file(char *filename, char program[ROWS][COLS]);
+int parse_instruction(char *instr, char *instr_bin_str);
+int parse_reg(char *reg_str);
+int parse_add(char *instr, char *instr_bin_str);
+int parse_mul(char *instr, char *instr_bin_str);
+int parse_sub(char *instr, char *instr_bin_str);
+int parse_div(char *instr, char *instr_bin_str);
+int parse_and(char *instr, char *instr_bin_str);
+int parse_or(char *instr, char *instr_bin_str);
+int parse_xor(char *instr, char *instr_bin_str);
 /* add additional helper functions to support other instructions */
-unsigned short int str_to_bin (char* instr_bin_str) ;
-int write_obj_file 			  (char* filename, unsigned short int program_bin[ROWS] ) ;
+/* add additional helper functions to support other instructions */
+unsigned short int str_to_bin(char *instr_bin_str);
+int write_obj_file(char *filename, unsigned short int program_bin[ROWS], int instr_count);
+void int_to_bin_str(int num, int bits, char *bin_str);
+void to_uppercase(char *str);
+#endif
diff --git a/assembler.c b/assembler.c
index efe906f..6da4af8 100644
--- a/assembler.c
+++ b/assembler.c
@@ -14,11 +14,50 @@
 #include <stdlib.h>
 #include "asm_parser.h"
 
-int main(int argc, char** argv) {
-
-	char* filename = NULL ;					// name of ASM file
-	char  program [ROWS][COLS] ; 			// ASM file line-by-line
-	char  program_bin_str [ROWS][17] ; 		// instructions converted to a binary string
-	unsigned short int program_bin [ROWS] ; // instructions in binary (HEX)
-
+int main(int argc, char **argv) {
+  if (argc < 2) {
+    printf("Usage: %s <assembly_file.asm>\n", argv[0]);
+    return 1;
+  }
+  char *filename = argv[1];  // name of ASM file
+  char program[ROWS][COLS];  // ASM file line-by-line
+  char program_bin_str[ROWS][17];  // instructions converted to a binary string
+  unsigned short int program_bin[ROWS];  // instructions in binary (HEX)
+  int num_lines = read_asm_file(filename, program);
+  if (num_lines < 0) {
+    return 1;
+  }
+  int instr_count = 0;
+  for (int i = 0; i < num_lines; i++) {
+    char *line = program[i];
+    char instr_bin_str[17];
+    int ret = parse_instruction(line, instr_bin_str);
+    if (ret == 1) {
+      strcpy(program_bin_str[instr_count], instr_bin_str);
+      program_bin[instr_count] = str_to_bin(instr_bin_str);
+      instr_count++;
+    } else if (ret == 0) {
+      // Skip empty or comment line
+      continue;
+    } else {
+      printf("Error parsing line %d: %s\n", i + 1, line);
+      return 1;
+    }
+  }
+  // Write the object file
+  char obj_filename[256];
+  strcpy(obj_filename, filename);
+  char *dot = strrchr(obj_filename, '.');
+  if (dot != NULL) {
+    strcpy(dot, ".obj");
+  } else {
+    strcat(obj_filename, ".obj");
+  }
+  int ret = write_obj_file(obj_filename, program_bin, instr_count);
+  if (ret < 0) {
+    printf("Error writing object file\n");
+    return 1;
+  }
+  printf("Successfully assembled %s to %s\n", filename, obj_filename);
+  return 0;
 }