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arendst / Tasmota

Alternative firmware for ESP8266 and ESP32 based devices with easy configuration using webUI, OTA updates, automation using timers or rules, expandability and entirely local control over MQTT, HTTP, Serial or KNX. Full documentation at
https://tasmota.github.io/docs
GNU General Public License v3.0
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Support for MCP2515 Stand-alone SPI CAN Bus Controller #7656

Closed Jojo-A closed 4 years ago

Jojo-A commented 4 years ago

Have you looked for this feature in other issues and in the docs?
Yes. Is your feature request related to a problem? Please describe.
No problem.

Describe the solution you'd like
Please see below.

Describe alternatives you've considered
None.

Additional context See below.

(Please, remember to close the issue when the problem has been addressed) For sure.

Hi, first of all I like to thank you sooo much for this project/firmware and the effort you've all put in it!

I like to contribute in making this project even more flexible and versatile by requesting support of the stand-alone CAN bus controller MCP2515 (or equivalent). The MCP2515 is a very broad available and relatively cheap CAN bus controller with SPI interface. It is available on tiny and cheap ready-to-use "evaluation boards" and also as shields for the Arduino platform

Usecase

A system of several CAN bus devices which I like to control/monitor remotely.

What I already have

I already created a very basic software (based on Arduino IDE), which runs on a Wemos ESP8266 board. It basically consists of the libraries:

This software does (basically) nothing else but converting CAN to MQTT and vice versa, there the CAN bus ID is part of the topic, and the CAN bus data field is the payload (divided by ";" or "," or "." or " " into single bytes). There is also a sign for data or RTR frames. So an example MQTT-to-CAN publish message to send data into the CAN bus could look like this: cmnd/MQTTtoCAN/98765/DAT/100;200;250;150;66;3;21;10 An example MQTT-to-CAN publish message to request data from a CAN bus device could look like this; cmnd/MQTTtoCAN/98765/RTR/ (empty payload)

The other direction (CAN-to-MQTT) works the same. So if the ESP receives a CAN message from a CAN bus device, it will be published to the MQTT broker as stat/MQTTtoCAN/98765/DAT/100;200;250;150;66;3;21;10

This software runs quite reliable. Remarkable limitation: it only supports extended identifiers (not so bad from my point of view) and it is just not as flexible and mature as Tasmota.

Idea regarding integration

I know, that this is not ideal for the data management used by Tasmota. So my idea is to handle it a little bit different: the CAN controller could appear as a "sensor", with three values:

  1. CAN ID
  2. frame format (data or RTR)
  3. data field

Every new incoming CAN message would trigger the "sensor" to be updated. So the telemetry data from Tasmota could look like: tele/MQTTtoCAN/SENSOR = {"Time":"yyyy-mm-dd","MCP2515":{"ID":"98765","Format":"Dat","Data":"100;200;250;150;66;3;21;10"}}

What we would need

What I can provide

For me it looks as if many things are already there and need "only" to be merged. Would it be worth it? What do you think?

Greetings, Jojo

stale[bot] commented 4 years ago

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

stale[bot] commented 4 years ago

This issue will be auto-closed because there hasn't been any activity for a few months. Feel free to open a new one if you still experience this problem.

pkkrusty commented 2 years ago

@Jojo-A any further interest in this? @kwiatek6324 was working on a similar project, but hasn't PRd anything yet.

Jojo-A commented 2 years ago

Hi, well basically yes. The work of @kwiatek6324 seems indeed similar to what I have thought about. But I personally think, that there is not so much general interest in that. So I understand why developers put not much effort in this...

kwiatek6324 commented 2 years ago

Sorry guys for delay, a lot of other thinkgs were going on. Created PR for this: https://github.com/arendst/Tasmota/pull/16684

Regards AK

arendst commented 2 years ago

PR now implemented in such a way that you have to select either define USE_CANSNIFFER or define USE_MCP2515.

Jojo-A commented 2 years ago

PR now implemented in such a way that you have to select either define USE_CANSNIFFER or define USE_MCP2515.

Okay, cool! I will give it a try when I have time! If it works as I hope, my own work regarding the MQTT-to-CAN gateway will be mostly obsolete ;)