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esp-idf-CANBus-Monitor

Monitor Canbus traffic.

USBCAN-V800

Background

Windows application for monitoring CANBus is published here.
This tool is designed to be used with this hardware.
bazaar487719_1

So, I made the hardware side with ESP32.

Application structure

+-------------+           +-------------+           +-------------+            +-------------+
| Windows     |           |   USB-TTL   |           |             |            | SN65HVD23x  |
| Application |<--(USB)-->|  Converter  |<--(TTL)-->|    ESP32    |<--(TWAI)-->|   CAN-BUS   |<--(CAN BUS)-->CAN Network
|             |           |             |           |             |            | Transceiver |
+-------------+           +-------------+           +-------------+            +-------------|

Software requirement

ESP-IDF V4.4/V5.x.
ESP-IDF V5.1 is required when using ESP32C6.

Hardware requirements

Windows PC
Windows applications can be downloaded from here.
- V7.10
- V7.20
- V8.00
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/C6
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
SN65HVD23x series has 230/231/232.
They differ in standby/sleep mode functionality.
Other features are the same.
Termination resistance
I used 150 ohms.

Wireing

SN65HVD23x		ESP32	ESP32-S2/S3	ESP32-C3/C6
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

Test Circuit

   +-----------+   +-----------+   +-----------+ 
   | 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)

Installation

git clone https://github.com/nopnop2002/esp-idf-CANBus-Monitor
cd esp-idf-CANBus-Monitor
idf.py set-target {esp32/esp32s2/esp32s3/esp32c3/esp32c6}
idf.py menuconfig
idf.py flash