can_sniffer/flip_monitor/README.md

CAN Monitor for Flipper Zero

Flipper Zero application for monitoring CAN sniffer statistics from Raspberry Pi 5 via UART.

Features

• Real-time display of CAN sniffer statistics
• Shows: IP address, total frames, pending frames, processed frames
• Connection status indicator
• Compatible with Unleashed firmware (0.84e and later)

Hardware Connection

Wiring (RPI5 <-> Flipper Zero)

RPI5 GPIO        Flipper Zero GPIO
-----------      -----------------
TX (GPIO 14) --> RX (Pin 14)
RX (GPIO 15) <-- TX (Pin 13)
GND          --> GND

Note: Cross TX/RX connections (RPI TX -> Flipper RX, RPI RX -> Flipper TX)

Flipper Zero GPIO Pinout

Pin 13 = TX (USART)
Pin 14 = RX (USART)
Pin 8/11/18 = GND

RPI5 GPIO (using /dev/ttyAMA0)

GPIO 14 = TX (Pin 8)
GPIO 15 = RX (Pin 10)
GND = Pin 6, 9, 14, 20, 25, 30, 34, 39

Building the Application

Prerequisites

1. Clone Flipper Zero firmware:

git clone --recursive https://github.com/DarkFlippers/unleashed-firmware.git
cd unleashed-firmware

2. Copy the flip_monitor folder to applications_user/:

cp -r /path/to/carpibord/flip_monitor applications_user/can_monitor

3. Create icon (10x10 PNG, 1-bit):

# Create icons/can_monitor.png (10x10 pixels, black & white)
# You can use any image editor or online tool

Build

# Build the FAP
./fbt fap_can_monitor

# Or build all external apps
./fbt fap_dist

The compiled .fap file will be in build/f7-firmware-D/.extapps/can_monitor.fap

Install

Copy the .fap file to your Flipper Zero SD card:

SD Card/apps/GPIO/can_monitor.fap

RPI5 Configuration

1. Enable UART

Add to /boot/config.txt:

enable_uart=1
dtoverlay=uart0

Reboot after changes.

2. Install pyserial

pip install pyserial

3. Configure CAN Sniffer

Add to can_sniffer/config.json:

{
  "flipper": {
    "enabled": true,
    "device": "/dev/ttyAMA0",
    "baudrate": 115200,
    "send_interval": 1.0
  }
}

Or use environment variables:

export CAN_SNIFFER_FLIPPER__ENABLED=true
export CAN_SNIFFER_FLIPPER__DEVICE=/dev/ttyAMA0

4. Run CAN Sniffer

cd can_sniffer/src
python main.py

Protocol

The RPI5 sends text-based statistics over UART:

STATS:ip=192.168.1.100,total=12345,pending=100,processed=12245\n

Fields:

• ip - RPI5 IP address
• total - Total CAN frames received
• pending - Frames in processing queue
• processed - Successfully processed frames

Troubleshooting

No connection

1. Check wiring (TX/RX crossed correctly)
2. Verify UART is enabled on RPI5: ls -la /dev/ttyAMA0
3. Check config: flipper.enabled = true
4. Test UART manually:

# On RPI5
echo "STATS:ip=test,total=1,pending=0,processed=1" > /dev/ttyAMA0

Permission denied on /dev/ttyAMA0

Add user to dialout group:

sudo usermod -a -G dialout $USER
# Then logout and login again

Flipper shows "Waiting..."

• Stats are sent every 1 second (configurable)
• Connection timeout is 5 seconds
• Check if CAN sniffer is running

License

MIT License