# ESP32-2432S028R Migration Summary

## Overview
Successfully migrated the DCC-Bench project from WiFi/WebServer control to touchscreen-based control using the ESP32-2432S028R module (ESP32 with ILI9341 TFT touchscreen).

## Hardware Configuration

### ESP32-2432S028R Module
- **Board**: ESP32-WROOM-32
- **Display**: ILI9341 TFT (320x240 pixels)
- **Touch**: XPT2046 resistive touchscreen
- **Pins Used**:
  - TFT MISO: GPIO 12
  - TFT MOSI: GPIO 13
  - TFT SCLK: GPIO 14
  - TFT CS: GPIO 15
  - TFT DC: GPIO 2
  - TFT BL (Backlight): GPIO 21
  - Touch CS: GPIO 22
  - Relay Control: GPIO 4
  - PWM/DCC_A: GPIO 18 (dual purpose)
  - DIR/DCC_B: GPIO 19 (dual purpose)
  - Motor BRAKE: GPIO 23

### LM18200 H-Bridge Driver (Dual Purpose)
The LM18200 serves as **BOTH** the DC motor controller AND DCC signal booster:
- **DC Analog Mode**: GPIO 18 sends PWM for speed, GPIO 19 sets direction
- **DCC Digital Mode**: GPIO 18 sends DCC signal A, GPIO 19 sends DCC signal B (inverted)
- Same hardware, different signals depending on mode selected
- LM18200 amplifies the 3.3V logic signals to track voltage (12-18V)

## Key Changes

### 1. PlatformIO Configuration (`platformio.ini`)
- **Changed**: Board target from `esp32doit-devkit-v1` to `esp32dev` for ESP32-2432S028R
- **Removed**: WiFi/WebServer libraries (ESPAsyncWebServer, AsyncTCP)
- **Added**: 
  - `bodmer/TFT_eSPI@^2.5.43` - Display driver
  - `paulstoffregen/XPT2046_Touchscreen@^1.4` - Touch controller
- **Added**: TFT_eSPI build flags for ILI9341 configuration

### 2. New Components

#### RelayController (`RelayController.h/cpp`)
- Controls relay on GPIO 27 for 2-rail/3-rail track switching
- Simple HIGH/LOW control
- State tracking and persistence through Config

#### TouchscreenUI (`TouchscreenUI.h/cpp`)
- Full graphical user interface with touch controls
- **Features**:
  - Power ON/OFF button (green/red indicator)
  - DCC/Analog mode toggle button (cyan/yellow)
  - 2-Rail/3-Rail selector button
  - Direction control (FWD/REV)
  - Horizontal speed slider (0-100%)
  - Status bar showing all current settings
- **Behavior**:
  - Switching from DCC to Analog (or vice versa) automatically powers off the system
  - All settings are saved to NVS (persistent storage)
  - Touch events mapped to screen coordinates with calibration

### 3. Modified Components

#### Config (`Config.h/cpp`)
- **Removed**: All WiFi-related configuration (`WiFiConfig` struct)
- **Added to SystemConfig**:
  - `bool is3Rail` - Track configuration (2-rail/3-rail)
  - `bool powerOn` - Power state tracking
- **Updated**: Save/load methods to persist new settings

#### Main (`main.cpp`)
- **Removed**: WiFi, WebServer, LEDIndicator components
- **Added**: TouchscreenUI, RelayController
- **Updated**: Setup sequence and main loop
- **Simplified**: Loop now only handles UI updates and motor/DCC control based on power state

### 4. Removed Files
- `include/WiFiManager.h`
- `src/WiFiManager.cpp`
- `include/WebServer.h`
- `src/WebServer.cpp`
- `include/LEDIndicator.h` (was already commented out)

## User Interface Layout

```
┌─────────────────────────────────────────────────┐
│ [POWER] [MODE ] [RAILS] [DIR ]                  │
│  ON/OFF  DCC/DC 2/3Rail FWD/REV                 │
│                                                  │
│              Speed: 45%                          │
│                                                  │
│  ╔════════════════○═════════════╗               │
│  ║                               ║  Speed Slider│
│  ╚═══════════════════════════════╝               │
│                                                  │
│ ┌─────────────────────────────────────────────┐ │
│ │ PWR:ON | Mode:DCC | 3-Rail | Addr:3         │ │
│ │ Speed:45% FWD                                │ │
│ └─────────────────────────────────────────────┘ │
└─────────────────────────────────────────────────┘
```

## Features Implemented

### ✅ Power Control
- Power ON/OFF button
- **Safety**: Power automatically turns OFF when switching between DCC and Analog modes
- Power state persisted in configuration

### ✅ Mode Switching
- Toggle between DCC and DC Analog control
- Visual indication (Cyan for DCC, Yellow for Analog)
- Automatic power-off on mode change prevents unsafe transitions

### ✅ Rail Configuration
- 2-Rail / 3-Rail selector
- Physical relay control on GPIO 27
- Energized = 3-Rail, De-energized = 2-Rail

### ✅ Speed Control
- Interactive horizontal slider
- Range: 0-100%
- Real-time speed updates to motor/DCC controller
- Visual feedback with active/inactive portions

### ✅ Direction Control
- Forward/Reverse toggle
- Updates motor or DCC direction based on current mode

### ✅ Persistent Storage
- All settings saved to ESP32 NVS (Non-Volatile Storage)
- Settings persist across power cycles
- Automatic save on every change

## Building and Uploading

```bash
# Install dependencies and build
pio run

# Upload to ESP32-2432S028R
pio run --target upload

# Monitor serial output
pio device monitor
```

## Next Steps / Future Enhancements

1. **DCC Address Entry**: Add touchscreen numeric keypad for changing DCC address
2. **Function Buttons**: Add DCC function controls (F0-F12) with toggle buttons
3. **Speed Presets**: Add quick-access speed buttons (25%, 50%, 75%, 100%)
4. **Track Current Monitoring**: Display track current if current sensor is added
5. **Emergency Stop**: Large red emergency stop button
6. **Locomotive Profiles**: Save/load different locomotive configurations

## Testing Checklist

- [ ] Display initializes correctly
- [ ] Touch calibration is accurate
- [ ] Power button toggles ON/OFF
- [ ] Mode switch changes DCC/Analog
- [ ] Mode switch automatically powers off
- [ ] Rail selector controls relay
- [ ] Speed slider adjusts output
- [ ] Direction button changes FWD/REV
- [ ] Settings persist after reboot
- [ ] DCC signals generated correctly (when powered on)
- [ ] DC motor control works (when powered on)
- [ ] Relay switches correctly

## Pin Reference

| Function | GPIO | Notes |
|----------|------|-------|
| PWM/DCC_A | 18 | DC: 20kHz PWM / DCC: Signal A |
| DIR/DCC_B | 19 | DC: Direction / DCC: Signal B |
| Motor Brake | 23 | Active LOW brake |
| Relay Control | 4 | HIGH=3-Rail, LOW=2-Rail |
| TFT MISO | 12 | SPI data in |
| TFT MOSI | 13 | SPI data out |
| TFT SCLK | 14 | SPI clock |
| TFT CS | 15 | Chip select |
| TFT DC | 2 | Data/Command |
| TFT Backlight | 21 | Backlight control |
| Touch CS | 22 | Touch chip select |

## Notes

- Motor PWM frequency: 20kHz (silent operation)
- Display orientation: Landscape (320x240)
- Touch type: Resistive (XPT2046)
- All configuration stored in NVS partition
- Pin assignments avoid conflicts with ESP32-2432S028R built-in peripherals