ATmega Microcontroller Code Submission Plugin for Moodle

This Moodle plugin provides a secure and automated validation system for student submissions in ATmega-based microcontroller lab courses. It supports file naming rules, integrity checks for compiled .hex files, timestamp validation, and silent warning flags for instructors — all designed to improve submission quality and reduce grading errors.

✨ Key Features

📁 Structured Submission Rules

• Requires exactly:
  • 1 PDF lab report
  • 1 ZIP archive of code + compiled files
• Files are automatically renamed to: LabX_studentID_semester.pdf LabX_studentID_semester.zip
• Prefix and semester are configurable per assignment.

🔍 File and Format Validation

• Enforces accepted file types (.zip, .pdf) and size limits:
• PDF: max 5 MB
• ZIP: max 50 MB
• ZIP file validation includes:
• No more than 50 folders
• No nested ZIPs
• No disallowed types (.exe, .php, .py, etc.)
• File timestamp checks

🧪 .hex File Validation

• Required .hex file count is configurable (e.g., 3+).
• Checks for:
• Empty .hex files (0 bytes)
• Uncompiled files (containing 00000)
• Missing embedded student ID (ASCII hex)
• Wrong student ID (suspicious reuse or mismatch)

🕒 Timestamp Integrity

• Compares .c / .h source file timestamps against compiled .hex files
• Detects and warns about mismatches
• Flags outdated .hex builds for manual attention

☠️ Cheating & Integrity Warnings (Instructor-Only)

• Any .hex file with a mismatched or missing student ID is silently flagged
• Stored in a dedicated table atmega_flags and shown only to teachers during grading
• Warnings are grouped as:
• ☠️ Cheating Suspicions
• ⚠️ Minor Issues (timestamps, no Makefile, etc.)

🛠 Developer & Admin Features

• Assignment-level settings:
• Default prefix (e.g., Lab1)
• Default semester (e.g., WS2025)
• Required minimum number of .hex files
• Color-coded student feedback (✅ success, ❌ blocking errors, ⚠️ warnings)
• Generates .txt validation report per submission
• Automatically renames uploaded files

📦 Backup & Restore

This plugin fully supports Moodle backup/restore for: - Student submission records (assignsubmission_atmegacode) - Attached ZIP and PDF files in the submission_files filearea

❗ The table atmega_flags, which stores teacher-only warning flags, is excluded from backups. These flags are auto-generated from submitted files and not essential for data integrity.

🧪 Usage

For Students

• Upload exactly:
• 1 .pdf report
• 1 .zip archive of source code and .hex files
• View inline feedback immediately after upload
• Fix and re-submit if validation fails

For Teachers

• Configure requirements when setting up the assignment
• View all uploaded files + any validation warnings
• Detect mismatches, cheating risks, and folder issues at a glance

⚙️ Installation

1. Place the plugin in the Moodle directory: mod/assign/submission/atmegacode/

2. Go to Site administration > Notifications to complete installation.

3. Enable the plugin inside each assignment under: Submission Types > MCU code submission (ATmega)

📝 License

This plugin is licensed under the GNU General Public License v3 or later.

👤 Authors

Developed by Ivan Volosyak and Tangat Baktybergen (2025)
For academic use at Hochschule Rhein-Waal and beyond.