First Release
This commit is contained in:
nopnop2002
@@ -1,2 +1,174 @@
|
||||
# esp-idf-can2http
|
||||
CANbus to http bridge using esp32
|
||||
CANbus to http bridge using esp32.
|
||||
It's purpose is to be a bridge between a CAN-Bus and a HTTP-Server.
|
||||
|
||||
I inspired from [here](https://github.com/c3re/can2mqtt).
|
||||
|
||||
|
||||
|
||||
|
||||
# Software requirement
|
||||
esp-idf v4.2-dev-2243 or later.
|
||||
Use twai(Two-Wire Automotive Interface) driver instead of can driver.
|
||||
|
||||
# Hardware requirements
|
||||
1. SN65HVD23x CAN-BUS Transceiver
|
||||
|
||||
|SN65HVD23x||ESP32|ESP32-S2||
|
||||
|:-:|:-:|:-:|:-:|:-:|
|
||||
|D(CTX)|--|GPIO21|GPIO20|(*1)|
|
||||
|GND|--|GND|GND||
|
||||
|Vcc|--|3.3V|3.3V||
|
||||
|R(CRX)|--|GPIO22|GPIO21|(*1)|
|
||||
|Vref|--|N/C|N/C||
|
||||
|CANL|--|||To CAN Bus|
|
||||
|CANH|--|||To CAN Bus|
|
||||
|RS|--|GND|GND|(*2)|
|
||||
|
||||
(*1) You can change using menuconfig.
|
||||
|
||||
(*2) N/C for SN65HVD232
|
||||
|
||||
2. Termination resistance
|
||||
I used 150 ohms.
|
||||
|
||||
|
||||
# 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)
|
||||
```
|
||||
|
||||
__NOTE__
|
||||
3V CAN Trasnceviers like VP230 are fully interoperable with 5V CAN trasnceviers like MCP2551.
|
||||
Check [here](http://www.ti.com/lit/an/slla337/slla337.pdf).
|
||||
|
||||
|
||||
# Installation for ESP32
|
||||
```
|
||||
git clone https://github.com/nopnop2002/esp-idf-can2http
|
||||
cd esp-idf-can2htp
|
||||
idf.py set-target esp32
|
||||
idf.py menuconfig
|
||||
idf.py flash
|
||||
```
|
||||
|
||||
# Installation for ESP32-S2
|
||||
```
|
||||
git clone https://github.com/nopnop2002/esp-idf-can2http
|
||||
cd esp-idf-can2http
|
||||
idf.py set-target esp32s2
|
||||
idf.py menuconfig
|
||||
idf.py flash
|
||||
```
|
||||
|
||||
# Configuration
|
||||
|
||||
|
||||
|
||||
## CAN Setting
|
||||
|
||||
|
||||
## WiFi Setting
|
||||
|
||||
|
||||
## HTTP Server Setting
|
||||
|
||||
|
||||
# Definition from CANbus to HTTP
|
||||
When CANbus data is received, it is sent by HTTP according to csv/can2http.csv.
|
||||
The file can2http.csv has three columns.
|
||||
In the first column you need to specify the CAN Frame type.
|
||||
The CAN frame type is either S(Standard frame) or E(Extended frame).
|
||||
In the second column you have to specify the CAN-ID as a __hexdecimal number__.
|
||||
In the last column you have to specify the HTTP-Path.
|
||||
Each CAN-ID and each HTTP-Path is allowed to appear only once in the whole file.
|
||||
|
||||
```
|
||||
S,101,/post
|
||||
E,101,/post
|
||||
S,103,/post
|
||||
E,103,/post
|
||||
```
|
||||
|
||||
When a Standard CAN frame with ID 0x101 is received, it is POST by PATH of "/post".
|
||||
When a Extended CAN frame with ID 0x101 is received, it is POST by PATH of "/post".
|
||||
http://{HTTP-Server-IP}:{HTTP-Server-Port}/post/{CAN-Data}
|
||||
|
||||
# HTTP Server Using Tornado
|
||||
```
|
||||
sudo apt install python3-pip python3-setuptools python3-magic
|
||||
python -m pip install -U pip
|
||||
python -m pip install -U wheel
|
||||
python -m pip install tornado
|
||||
cd tornado
|
||||
python can.py
|
||||
```
|
||||
|
||||
|
||||
# HTTP Server Using Flask
|
||||
```
|
||||
sudo apt install python3-pip python3-setuptools python3-magic
|
||||
python -m pip install -U pip
|
||||
python -m pip install -U wheel
|
||||
python -m pip install -U Werkzeug
|
||||
python -m pip install flask
|
||||
cd flask
|
||||
python can.py
|
||||
```
|
||||
|
||||
|
||||
|
||||
|
||||
# List data Using Brouser
|
||||
Open your browser and put the IP address in the address bar.
|
||||
|
||||
|
||||
|
||||
# Troubleshooting
|
||||
There is a module of SN65HVD230 like this.
|
||||
|
||||
|
||||
There is a __120 ohms__ terminating resistor on the left side.
|
||||
|
||||
|
||||
I have removed the terminating resistor.
|
||||
And I used a external resistance of __150 ohms__.
|
||||
A transmission fail is fixed.
|
||||
|
||||
|
||||
If the transmission fails, these are the possible causes.
|
||||
- There is no receiving app on CanBus.
|
||||
- The speed does not match the receiver.
|
||||
- There is no terminating resistor on the CanBus.
|
||||
- There are three terminating resistors on the CanBus.
|
||||
- The resistance value of the terminating resistor is incorrect.
|
||||
- Stub length in CAN bus is too long. See [here](https://e2e.ti.com/support/interface-group/interface/f/interface-forum/378932/iso1050-can-bus-stub-length).
|
||||
|
||||
|
||||
Reference in New Issue
Block a user