monirul.pathan
Posts: 3
Joined: Wed Sep 05, 2012 9:46 pm

Roller shade control over 433mhz

Sat May 06, 2017 9:10 pm

Hi,
I'm trying to decode and control my somewhat DIY roller shades through the pi. I'm stuck trying to decode the signal the remote is sending out. I'm trying to use the rtl_433 library to decode the signal but its coming up with an empty string:

Code: Select all

pi@pi:~/rtl_433 $ rtl_433 -a
...
*** signal_start = 1532705, signal_end = 1739189
signal_len = 206484,  pulses = 645
Iteration 1. t: 668    min: 127 (630)    max: 1210 (15)    delta 1805
Iteration 2. t: 668    min: 127 (630)    max: 1210 (15)    delta 0
Pulse coding: Short pulse length 127 - Long pulse length 1210
Short distance: 76, long distance: 155, packet distance: 610
p_limit: 668
bitbuffer:: Number of rows: 16
[00] {1} 80 : 1
[01] {43} 00 00 00 00 00 20 : 00000000 00000000 00000000 00000000 00000000 001
[02] {43} 00 00 00 00 00 20 : 00000000 00000000 00000000 00000000 00000000 001
[03] {43} 00 00 00 00 00 20 : 00000000 00000000 00000000 00000000 00000000 001
[04] {43} 00 00 00 00 00 20 : 00000000 00000000 00000000 00000000 00000000 001
[05] {43} 00 00 00 00 00 20 : 00000000 00000000 00000000 00000000 00000000 001
[06] {43} 00 00 00 00 00 20 : 00000000 00000000 00000000 00000000 00000000 001
[07] {43} 00 00 00 00 00 20 : 00000000 00000000 00000000 00000000 00000000 001
[08] {43} 00 00 00 00 00 20 : 00000000 00000000 00000000 00000000 00000000 001
[09] {43} 00 00 00 00 00 20 : 00000000 00000000 00000000 00000000 00000000 001
[10] {43} 00 00 00 00 00 20 : 00000000 00000000 00000000 00000000 00000000 001
[11] {43} 00 00 00 00 00 20 : 00000000 00000000 00000000 00000000 00000000 001
[12] {43} 00 00 00 00 00 20 : 00000000 00000000 00000000 00000000 00000000 001
[13] {43} 00 00 00 00 00 20 : 00000000 00000000 00000000 00000000 00000000 001
[14] {43} 00 00 00 00 00 20 : 00000000 00000000 00000000 00000000 00000000 001
[15] {42} 00 00 00 00 00 00 : 00000000 00000000 00000000 00000000 00000000 00

I'm using a RTL2838 SDR


I've attached the wave that I've recorded and my attempt at manually decoding it. Any idea how to get rtl_433 to decode it ? Ultimately I'd like to use 433Utils or similar to be able to play it back over some inexpensive 433 transmitters.

Thank you!!!

---------------------
Roller shade motor + remote:
http://www.ebay.ca/itm/28cm-1-5A-12V-El ... Sw03lY6y4m
rtl_433: https://github.com/merbanan/rtl_433
433Utils: https://github.com/ninjablocks/433Utils
Attachments
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Ronaldlees
Posts: 294
Joined: Sat Apr 16, 2016 4:28 pm
Location: North Carolina, US
Contact: Website

Re: Roller shade control over 433mhz

Mon May 08, 2017 1:28 pm

Since nobody else is answering ...

Based on my quick reading of a few articles on some websites - it seems that more often than not these remotes use proprietary protocols, as do the radio-motors (blinds). From my reading, it seems there are only a couple open protocols. I could guess that unless your unit uses one of the open protocols, you'll not likely be able to decode anything directly with your Pi. I haven't yet purchased any of this stuff myself, but since nobody else was looking into it for you, I thought I'd mention what I read. You've sparked my interest about using these things, so I hope someone else can chime in here and illucidate further ...

I looked at your ebay purchase, and the included info seems not to mention which protocols are used, or what it may be compatible with. There seems to be a real hodge-podge of competing, often proprietary, inter-dependent stuff for sale. Looks like a buyer-beware market.

I noticed that the "opennethome" and "domoticz" sites list compatibility with certain protocols (open ones maybe, but I don't know). The first of those sites mentions use of an RF433 Jeelinks USB dongle to control 433 MHz radio-motors, and the second mentions the use of the RFXCom USB dongles to control the blind's radio-motor. In both cases the software was loaded onto a Pi2. The software let's you select a *specific* blind's (by brand/model) radio-motor, from what I read. The example I read was for rollertrol blinds IIRC. Can't vouch for any of it of course, but it looks interesting.

With an open protocol, the source code must contain the decode procedure (unless it's via a blob device) - since the dongles are generic 433 Mhz AFAIK. I may be completely off-base here, but am interested in learning more about these things ...
I am the Umbrella man

Eamonn54
Posts: 18
Joined: Fri Mar 03, 2017 4:09 pm

Re: Roller shade control over 433mhz

Mon May 08, 2017 5:39 pm

This may, or may not, be relevant, but, please be aware, that the Amateur Radio spectrum, and indeed, Military Radio Spectrum, use 433 MHz, for communications.
You may experience some interference, especially if you are in an area where there is an active 'radio repeater'.
Usage by Radio Amateurs, may cause slight problems with your system, and, indeed, you may also be causing interference to them. More likely to be the former, as I am pretty sure the power used for your system will be extremely low.

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Ronaldlees
Posts: 294
Joined: Sat Apr 16, 2016 4:28 pm
Location: North Carolina, US
Contact: Website

Re: Roller shade control over 433mhz

Mon May 08, 2017 11:20 pm

Eamonn54 wrote:This may, or may not, be relevant, but, please be aware, that the Amateur Radio spectrum, and indeed, Military Radio Spectrum, use 433 MHz, for communications.
You may experience some interference, especially if you are in an area where there is an active 'radio repeater'.
Usage by Radio Amateurs, may cause slight problems with your system, and, indeed, you may also be causing interference to them. More likely to be the former, as I am pretty sure the power used for your system will be extremely low.
Right, depending upon which country you're a resident of, you may be subject to restrictions. I assumed that the OP resided in a country that allowed for home automation signals on 433 MHz. The blinds manufacturers have different frequencies available for different countries - if I remember correctly what I read on their pages.

Looks like maximum power for home automation in countries that allow it on 433 MHz is 10 mW. Suspect that's not too much of an interference problem on TX. But, as you say could be an issue on RX.
I am the Umbrella man

monirul.pathan
Posts: 3
Joined: Wed Sep 05, 2012 9:46 pm

Re: Roller shade control over 433mhz

Tue May 09, 2017 5:54 am

Ronaldlees wrote: I noticed that the "opennethome" and "domoticz" sites list compatibility with certain protocols (open ones maybe, but I don't know). The first of those sites mentions use of an RF433 Jeelinks USB dongle to control 433 MHz radio-motors, and the second mentions the use of the RFXCom USB dongles to control the blind's radio-motor. In both cases the software was loaded onto a Pi2. The software let's you select a *specific* blind's (by brand/model) radio-motor, from what I read. The example I read was for rollertrol blinds IIRC. Can't vouch for any of it of course, but it looks interesting.

YEASSSSSSSSSSS!!!!
Ronaldlees you sir have made my day! Thank you for the perfect lead there!

RollerTrolBlind had a device that looked exactly like my remote so that was definitely the right track coupled with opennethome.

opennethome was relatively simple to set up. However, I did not want to order a new usb transceiver when I had a perfectly good 433mhz transmitter already hooked up to the Pi. So down the gpio rabbit hole. Opennethome has a bit banger interface, and coupled with pibang, I was able to get it set up after an extremely slow install and compile.

The biggest head scratcher was that I was looking for /dev/rfbb device according to the instructions but it really installed it under /dev/pibang. Once that was sorted, it was a quick jump to get the motor programmed using the "RollerTrolBlind" device.

After 4 days I can finally sleep in peace :lol:

Also, I'm using a paperclip for an antenna and just need the signal to go 6 feet over. The readings I'm seeing from the SDR shows that its putting out a fraction of the power compared to the transmitter that came with it. However, I doubt the transmitter is really officially certified. I'll look more into regulation for the band in Canada just to be safe though.

This is the transmitter I'm using:
https://www.sparkfun.com/products/10534

Ronaldlees wrote:
Eamonn54 wrote:This may, or may not, be relevant, but, please be aware, that the Amateur Radio spectrum, and indeed, Military Radio Spectrum, use 433 MHz, for communications.
You may experience some interference, especially if you are in an area where there is an active 'radio repeater'.
Usage by Radio Amateurs, may cause slight problems with your system, and, indeed, you may also be causing interference to them. More likely to be the former, as I am pretty sure the power used for your system will be extremely low.
Looks like maximum power for home automation in countries that allow it on 433 MHz is 10 mW. Suspect that's not too much of an interference problem on TX. But, as you say could be an issue on RX.
RX does not seem to be too much of an issue thankfully. I've only been seeing the occasional blip when my neighbors use their car remotes.

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