ad-hoc network for pimatic necessary ? - Update: Proof of Concept working

---

One of the most requested features is a ad-hoc method for pimatic. You can allmost do anything withe API to acomplish some sort of ad-hoc network. But is a second pi/pimatic allwaus needed ?

At the moment I’m fiddling with the homeduino-esp8266-node, but need to solder my level shifter first.
Then it crossed my mind. If we could ad a RF sender to the current homeduino-esp8266-node, setup a TCP server on the ESP it should be possible to let pimatic talk to the ESP module.

Currently the homeduino-esp8266-node will detect RF network and when it looks like a valid protocol it is transmitted over the API to the homeduino plugin. The homeduino plugin will analyze the bits to determine if it is a known protocol and if so … do some stuff.
How about reversing this?
Add a option to the homeduino that some sort of device is handled by the homeduino-esp8266-node. When this device is triggered (for example: ON) it is not passed to the arduino (connected to the pi) but the bits are passed to the ESP through the TCP server. The ESP receives the entire protocol in bits and all it has to do is blast it in the air with the connected RF sender.
Whenever a new protocol is added to the homeduino plugin , you can send it to the homeduino-esp8266-node, because same as receiving : it doesn’t need any knowledge about the protocols.

I don’t have the skills to accomplish this, but perhaps someone can start with this idea ?

@koffienl This has been on my personal wish/development list for a while, sadly I currently do not have time to experiment with this. Shouldn’t be too hard to do though as the homeduino source should easily compile for the ESP. Such a device would be a great wifi-backed 433MHz accesspoint for the upper floor, attick, garden, etc.

@koffienl Great idea, however would it also be possible to sent specific RF commands to specific ESP modules. This would really expand the range and would not create a burst to all ESP’s in the neighborhood.

You are right, when buidling this you need to make it future proof. So you can define what RF device needs to go to what ESP.

or its possible to build a mysensors-node to send/receive homeduino signals

So i can put a node on every floor

I think another option (probably similar to what @koffienl and you guys have in mind) is to setup ESP8266 as a transparent serial line bridge. A few guys contributing to the J5 project are currently developing this to simplify the setup of remote J5 nodes. The bridge simply mediates messages between an UDP socket and the serial line interface of the ESP8266 connected to the arduino. (An alternative project in this context is esp-link which provides a tcp to serial bridge.) At the other end, you have a so-called “udp-serial” serialport which is the counterpart of the bridge to provide node-serialport interface to the application. With this approach you could also do broadcasts, i.e. send commands to multiple remote homeduino nodes (ESP8266 bridge plus Arduino). Think of this as cutting the USB cable, putting wifi in between (and potentially multiplexing messages to multiple Homeduino nodes if it is not just 1:1)

The changes required to hook this in pimatic-homeduino should be fairly minimal. It is basically about implementing a new driver for the homeduino Board which is part of homeduinojs. If you look at the serialport driver for the Board thats just about 100 lines of code and, obviously, it is using node-serialport.

Please let me know what you think. For now, it is just a rough idea.

+--------------------------+                           +--------------------------------+
|                          |                           |                                |
| pimatic+homeduino plugin |                           | Remote Homeduino Node          |
|             +------------+                           +--------------------------------+
|             | udp-serial | +---------------------->  | ESP8266 transparent bridge     |
|             |            |                           |                                |
+-------------+------------+                           +--------------------------------+

I like that idea
Only issue : when using multiple ESP’s you do not want all of them receive the ‘rf over TCP’ package becuase this will blast the environment with RF collision. You should be able to tell in the pimatic config what ESP should handle the specific RF device.

@koffienl Yes, you may run into problems if you have multiple remote nodes.
It would be worth giving at try though.

A few links:

• http://hackaday.com/2015/09/18/transparent-esp8266-wifi-to-serial-bridge/
• https://github.com/jeelabs/esp-link - that’s a tcp to serial bridge, however
• https://gist.github.com/ajfisher/5fe60fe7d8c49b3223f0 - udp to serial bridge for J5 - work in progress. Unfortuanely the guys haven’t setup a project yet

First Proof of Concept working!

https://www.youtube.com/watch?v=HbUVxnl6MgQ

There is no arduino connected to the Raspberry Pi, pimatic is talking directly to the ESP over wifi. the ESP chip receives the RF info and use the RF sender to broadcast the pulses.
Still a lot of work to do and a lot to test … but there is progress!

@koffienl said:

First Proof of Concept working!

Wow! That’s great! Which approach do you have taken? Did you take up on the ide of implementing a udp-serialport and having the ESP acting as a transparent bridge between UDP and the Arduino serial interface? Just wondering.

No (not yet). I lik small babysteps that I understand.
For now it is a simpel serial over TCP connection from Linux to ESP. Basicly the same as a the serial bridge but a different and simpeler approach.

@koffienl said:

small babysteps that I understand.
For now it is a simpel serial over TCP connection from Linux to ESP.

Ok, fair enough. I think it is the right approach to keep things as simple as possible and than add the sugar later

If the idea of using an IP “serialport” transport hooked into homeduinojs is feasable, there are ready-to-use implementations for this, i.e. for TCP: etherport-client and etherport (server-side) and for UDP it is udp-serial (this may needs some touch-up imo). I have also written a small add-in to debug serialport comms in javascript. It hexdumps sent and received messages on the console.

https://github.com/mwittig/etherport-client
https://github.com/mwittig/etherport
https://github.com/monteslu/udp-serial
https://github.com/mwittig/node-serialport-debug (to be released)

Nice
I think this is a bridge to far for my limitted coding skills. The benefit of my current approach is that it works without any modification to pimatic or adding a plugin.
Next step is to get receive working, but I have to solder a logic converter for that part.

@koffienl said:

For now it is a simpel serial over TCP connection from Linux to ESP.

Ah, it is device you have setup in the OS, right? Which ESP firmware do you use? Is it your own project or is esp-link?

Yes, a pesudo-TTY from OS to the ESP. the code on the ESP is something i wrote specificly for this project.

I’m adopting the homeduino-esp8266-node code from @sweetpi for receiving RF on a ESP.
It works a bit … I can receive signals from a cheap action remote, but can’t receive KaKu at all. Simply nothin is detected.
Tried with a logic level converte (bi-directional) but then I don’t receive anything at aal. @incmve is also testing with ESP and RF receiver but experience exact the same issues.

Before we keep looking into the wrong direction, can someone confirm they have actually received KaKu signals with https://github.com/pimatic/homeduino-esp8266-node ? What hardware did you use, ow was the receiver wired to the ESP?

Edit : created the following test setup:

RF 433Mhz (superheterodyne) with data pin to GPIO-0 on ESP. Powered the RF receiver directly with regulated 5v. Powered the ESP with regulated 3.3v.
I can receive eurodomest remote without a problem, but still not KaKu. I’m starting to beleive it is not a power issue but perhaps something with timings on the much faster 80 Mhz ESP ?

I have addedd receive of RF to my test. Should work and should properly send to Pimatic what is received. Can’t test right now because KaKu issue and no Pimatic at work

@koffienl said:

I can receive eurodomest remote without a problem, but still not KaKu.

Same here! I can receive eurodomest and my no-name weather13 station, but nothing on KAKU/COCO.

That is interesting. Normally the library should work exact the same on the esp8266. Eventually you must change the buffer size because it isn’t declared for the esp. (in RFControl.cpp)

Sending KaKu is not even truggering the RFControl::hasData event. Will take a look later this evening.