Added python version of pass 1 and pass 2 assembler (a1).

Codes/Python version/Assignment-A1 (Assembler)/Code-A1.py

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+# Assignment A1 - Pass 1 and pass 2 assembler
+# Example Opcode Table (OPTAB)
+OPTAB = {
+    "LOAD": "01",
+    "STORE": "02",
+    "ADD": "03",
+    "SUB": "04",
+    "JMP": "05"
+}
+
+# Example Assembler Directives
+DIRECTIVES = ["START", "END", "WORD", "RESW", "RESB"]
+
+# Symbol Table (SYMTAB) and Intermediate Code
+SYMTAB = {}
+intermediate_code = []
+
+# Pass-I: Generates the symbol table and intermediate code
+def pass1(input_lines):
+    locctr = 0
+    start_address = 0
+    for line in input_lines:
+        label, opcode, operand = parse_line(line.strip())
+
+        if opcode == "START":
+            start_address = int(operand)
+            locctr = start_address
+            intermediate_code.append((locctr, label, opcode, operand))
+            continue
+
+        # Process label
+        if label:
+            if label in SYMTAB:
+                print(f"Error: Duplicate symbol {label}")
+            SYMTAB[label] = locctr
+
+        # Process opcode
+        if opcode in OPTAB:
+            intermediate_code.append((locctr, label, opcode, operand))
+            locctr += 3  # Assume all instructions are 3 bytes
+        elif opcode in DIRECTIVES:
+            if opcode == "WORD":
+                locctr += 3
+            elif opcode == "RESW":
+                locctr += 3 * int(operand)
+            elif opcode == "RESB":
+                locctr += int(operand)
+            elif opcode == "END":
+                intermediate_code.append((locctr, label, opcode, operand))
+                break
+        else:
+            print(f"Error: Invalid opcode {opcode}")
+
+    return start_address, intermediate_code
+
+# Parse a line of input (splits line into label, opcode, operand)
+def parse_line(line):
+    parts = line.split()
+    label = parts[0] if len(parts) == 3 else None
+    opcode = parts[1] if len(parts) == 3 else parts[0]
+    operand = parts[2] if len(parts) == 3 else parts[1] if len(parts) == 2 else None
+    return label, opcode, operand
+
+# Pass-II: Generates the final machine code
+def pass2(start_address, intermediate_code):
+    final_code = []
+    for locctr, label, opcode, operand in intermediate_code:
+        if opcode in OPTAB:
+            machine_code = OPTAB[opcode]
+            if operand in SYMTAB:
+                address = format(SYMTAB[operand], '04X')  # 4-digit hex address
+            else:
+                address = '0000'  # Default if symbol not found
+            final_code.append(f"{locctr:04X} {machine_code} {address}")
+        elif opcode == "WORD":
+            final_code.append(f"{locctr:04X} {int(operand):06X}")
+        elif opcode == "RESW" or opcode == "RESB":
+            final_code.append(f"{locctr:04X} ----")
+        elif opcode == "END":
+            final_code.append(f"{locctr:04X} END")
+    return final_code
+
+# Main function to read the input file and run both passes
+def main():
+    # Read the assembly code from input.txt
+    with open("assemblerIP.txt", "r") as file:
+        input_lines = file.readlines()
+
+    # Run Pass-I
+    start_address, intermediate_code = pass1(input_lines)
+
+    # Display Symbol Table and Intermediate Code
+    print("\nPass-I Output:")
+    print("Symbol Table (SYMTAB):", SYMTAB)
+    print("\nIntermediate Code:")
+    for entry in intermediate_code:
+        print(entry)
+
+    # Run Pass-II
+    final_code = pass2(start_address, intermediate_code)
+
+    # Display Final Machine Code
+    print("\nPass-II Output (Final Machine Code):")
+    for code in final_code:
+        print(code)
+
+# Run the main function
+if __name__ == "__main__":
+    main()

Codes/Python version/Assignment-A1 (Assembler)/assemblerIP.txt

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+COPY START 1000
+FIRST LOAD ALPHA
+ADD BETA
+STORE GAMMA
+ALPHA WORD 5
+BETA RESW 1
+GAMMA RESB 1
+END FIRST