🧪 Automatic Tissue Processor (ATP) – Embedded System

📖 Overview

The Automatic Tissue Processor (ATP) is a medical laboratory device used in pathology labs to process biopsy tissues for further examination.
This project implements a cost-effective embedded solution using a PIC16F877A microcontroller, RTC module, LCD, keypad interface, and EEPROM-based configuration.

It features:

• Real-time clock tracking and scheduling of processing cycles.
• Recovery mechanism after unexpected power outages.
• Configurable time schedules for each tissue beaker.
• User interaction via a 4x3 matrix keypad and LCD menus.

---

⚙️ Hardware Components

• PIC16F877A Microcontroller
• 16x2 LCD Display
• 4x3 Keypad Matrix
• RTC (DS1307 / compatible) via I2C
• EEPROM (internal) for saving settings & recovery states
• Relay / Motor drivers for mechanical control
• Power outage detection circuit (connected to POWER_OUT_PIN)

---

🖥️ Software Features

1. Real-Time Clock Management

   • Uses I2C to interface with RTC (time & date tracking).
   • Time displayed in HH:MM:SS format on LCD.

2. Menu System (via LCD + Keypad)

   • Main Menu: Start, Test, Time, Configure.
   • Start Mode: Runs the processing sequence for selected beakers.
   • Test Mode: Manual control for movement (UP, DOWN, Next, Home, etc.).
   • Time Mode: View or Set system date & time.
   • Configure Mode:
     • Auto-start scheduling.
     • Per-beaker processing time configuration.
     • View saved configurations.

3. Power Outage Handling

   • Detects power failure using input pin.
   • Saves current state (beaker, remaining time) into EEPROM.
   • Restores and continues automatically after power recovery.

4. EEPROM Persistence

   • Stores auto-start time.
   • Stores per-beaker time configurations.
   • Saves system state in case of failure.

---

🔧 File Structure

/ATP-Firmware
 ├── main.c             # Main firmware with menus & control logic
 ├── lcd.c              # LCD driver
 ├── rtc.c              # RTC read/write functions
 ├── README.md          # Documentation

---

🚀 How It Works

1. Startup

   • System initializes LCD & RTC.
   • Displays main menu.

2. Processing Cycle

   • User selects Start → Beaker A begins.
   • System calculates required time for each beaker using current RTC values + EEPROM config.
   • Moves sequentially through beakers (A → B → ... → M).

3. During Power Outage

   • POWER_OUT_PIN detects failure.
   • State (current beaker, remaining time) is written to EEPROM.
   • On recovery, system restores from saved state and continues.

---

🛠️ Development Environment

• Compiler: CCS C for PIC (MPLAB also supported with minor adjustments)
• Target MCU: PIC16F877A (20 MHz crystal)
• Communication: I2C (RTC), RS232 (debugging), GPIO (LCD & Keypad)

---

📋 Example LCD Screens

Main Menu

1:Start       3:Time
2:Test        4:Configure

Start Menu

Beaker (A) Time:12:34:56
CupB:12:40:00   #:STOP

Error Handling

POWER ERROR!
IN:0

---

✅ Key Contributions

• Embedded Software Design (bare-metal C on PIC16F877A).
• Hardware Integration (LCD, Keypad, RTC, EEPROM).
• System Resilience (Power-out recovery).
• User-friendly interface for lab technicians.