🚀 DEUARC Emulator

DEUARC Emulator is a C-based emulator for a custom, minimal CPU architecture called DEUARC (DEU Electronic Universal Automatic Reduced Computer). It was developed as part of the CME 2206 Computer Architecture course at Dokuz Eylül University to learn low-level programming, instruction decoding, and memory management in C.

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🛠 Project Summary

• Project Title: DEUARC Emulator
• Institution: Dokuz Eylül University, Faculty of Engineering, Computer Engineering
• Course: CME 2206 – Computer Architecture
• Date: June 2025

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🚀 Features

• Instruction Fetch & Decode

  • Reads fixed-width 11-bit instructions from a text file
  • Parses opcode, registers, and immediate fields

• Instruction Set Support

  • Control: HLT, JMP, JMR, CAL, RET
  • Arithmetic & Logic: DBL, DBT, ADD, NOT, XOR, INC
  • Memory & I/O: LD, ST, IO, TSF

• Memory Model

  • Instruction Memory: 32 words of 11 bits
  • Data Memory: 16 words of 11 bits
  • Stack Memory: 16 words of 11 bits

• Register File

  • Program Counter (PC)
  • Stack Pointer (SP)
  • Address Register (AR)
  • Instruction Register (IR)
  • Input & Output Registers (INPR, OUTR)
  • 3 General-Purpose Registers (R0, R1, R2)

• Execution Loop

  • Fetch → Decode → Execute until HLT
  • Simple PC push/pop on CAL/RET

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📦 System Architecture

emulator.c       # Main driver: CPU state init, memory loading, execution loop
Memory          # Instantiates instruction, data, and stack memories as arrays
CPU             # Holds registers (PC, SP, AR, IR, INPR, OUTR, R[]), and state
fetch()         # Copies next instruction into IR, increments PC safely
decode()        # Extracts Q, opcode, Rd, S1, S2 from IR
execute()       # Matches opcode and performs the operation on registers/memory
load_memory()   # Reads binary words from file into memory arrays
init_cpu()      # Zeroes CPU struct and initializes registers
get_reg_ptr()   # Returns pointer to register array element by code

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🛠️ Build & Run

Using GCC

gcc emulator.c -o deuarc_emulator

Run the Emulator

1. With both instruction & data files

   ./deuarc_emulator instructions.txt data.txt

2. With only instruction file

   ./deuarc_emulator instructions.txt

Each file should contain fixed-width 11-character binary strings (0/1). Instruction memory max 32 words; data memory max 16 words.

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⚙️ Algorithm Complexity

• Time: O(T × N) per run, where T is number of cycles until HLT and N is number of opcodes.
• Space: O(1) additional beyond fixed memory sizes.

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🔮 Future Improvements

• Complete Opcode Logic: Implement all arithmetic and memory operations fully (ADD, XOR, IO, ST/LD variations).
• Error Handling: Bounds checks for PC/SP overflow, file format validation, and invalid opcode detection.
• CMake Support: Add CMakeLists.txt for cross-platform builds.
• Unit Tests: Create automated tests for each opcode and memory operation.

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📂 File Overview

emulator.c          # Refactored source code (fetch, decode, execute, etc.)
instructions.txt    # Example instruction memory input
data.txt            # Example data memory input (optional)

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📧 Contact

Email: [email protected]