Monitor Canbus traffic.
Windows application for monitoring CANBus is published here.
This tool is designed to be used with this hardware.
So, I made the hardware side with ESP32.
+-------------+ +-------------+ +-------------+ +-------------+
| Windows | | USB-TTL | | | | SN65HVD23x |
| Application |<--(USB)-->| Converter |<--(TTL)-->| ESP32 |<--(TWAI)-->| CAN-BUS |<--(CAN BUS)-->CAN Network
| | | | | | | Transceiver |
+-------------+ +-------------+ +-------------+ +-------------|
esp-idf v4.4/v5.0.
This is because this version supports ESP32-C3.
-
Windows PC
Windows applications can be downloaded from here. -
USB-TTL Converter
ESP32 development board has USB.
This USB connects to Linux and is used for writing the firmware and displaying the LOG.
Need converter to connect with Windows PC.
Converter | ESP32 | ESP32-S2/S3 | ESP32-C3 | ||
---|---|---|---|---|---|
RXD | -- | GPIO4 | GPIO17 | GPIO4 | (*1) |
TXD | -- | GPIO5 | GPIO18 | GPIO5 | (*1) |
GND | -- | GND | GND | GND |
(*1) You can change using menuconfig. But it may not work with other GPIOs.
-
SN65HVD23x CAN-BUS Transceiver
-
Termination resistance
I used 150 ohms.
SN65HVD23x | ESP32 | ESP32-S2/S3 | ESP32-C3 | ||
---|---|---|---|---|---|
D(CTX) | -- | GPIO21 | GPIO19 | GPIO0 | (*1) |
GND | -- | GND | GND | GND | |
Vcc | -- | 3.3V | 3.3V | 3.3V | |
R(CRX) | -- | GPIO22 | GPIO20 | GPIO1 | (*1) |
Vref | -- | N/C | N/C | N/C | |
CANL | -- | To CAN Bus | |||
CANH | -- | To CAN Bus | |||
RS | -- | GND | GND | GND | (*2) |
(*1) You can change using menuconfig. But it may not work with other GPIOs.
(*2) N/C for SN65HVD232
+-----------+ +-----------+ +-----------+
| Atmega328 | | Atmega328 | | ESP32 |
| | | | | |
| Transmit | | Receive | | 21 22 |
+-----------+ +-----------+ +-----------+
| | | | | |
+-----------+ +-----------+ | |
| | | | | |
| MCP2515 | | MCP2515 | | |
| | | | | |
+-----------+ +-----------+ | |
| | | | | |
+-----------+ +-----------+ +-----------+
| | | | | D R |
| MCP2551 | | MCP2551 | | VP230 |
| H L | | H L | | H L |
+-----------+ +-----------+ +-----------+
| | | | | |
+--^^^--+ | | +--^^^--+
| R1 | | | | R2 |
|---+-------|-------+-------|-------+-------|---| BackBorn H
| | |
| | |
| | |
|-----------+---------------+---------------+---| BackBorn L
+--^^^--+:Terminaror register
R1:120 ohms
R2:150 ohms(Not working at 120 ohms)
git clone https://github.com/nopnop2002/esp-idf-CANBus-Monitor
cd esp-idf-CANBus-Monitor
idf.py set-target {esp32/esp32s2/esp32s3/esp32c3}
idf.py menuconfig
idf.py flash
CAN received messages can be broadcast using UDP.
You can use udp-receive.py
as the receiver.
- Add ESP32 to CanBus.
- Write firmware to ESP32.
- Connect ESP32 and Windows PC using USB-TTL Converter.
- Start a Windows application.
See here.
Official document is here.