Irobot Roomba IR signal receive

Thread Starter

LAOADAM

Joined Nov 21, 2018
862
Hi,
I have a Irobot Roomba 4230, with Virtual Wall and a remote, I just wonder is the signals from them be able to identified? such as by SONY or other Protocol?
Thanks
Adam

roomba.jpg
 

MrChips

Joined Oct 2, 2009
30,708
Most IR remotes are easily identifiable.

Firstly, you need a raw IR diode to detect the carrier frequency. Commonly used frequencies are 38kHz and 40kHz.
Once you have determined the frequency you can choose an off-the-shelf IR receiver module that will output the digital signal.
This will be a sequence of low and high voltages.

By examining the received signal on an oscilloscope you can determine the bit period.
From this you can program a simple MCU to capture and display the bits.

I show a simple demo here MSP430 - TV Remote Decoder.
 

Thread Starter

LAOADAM

Joined Nov 21, 2018
862
Most IR remotes are easily identifiable.

Firstly, you need a raw IR diode to detect the carrier frequency. Commonly used frequencies are 38kHz and 40kHz.
Once you have determined the frequency you can choose an off-the-shelf IR receiver module that will output the digital signal.
This will be a sequence of low and high voltages.

By examining the received signal on an oscilloscope you can determine the bit period.
From this you can program a simple MCU to capture and display the bits.

I show a simple demo here MSP430 - TV Remote Decoder.
Thank you MrChips.
I'll check the link.
 

Thread Starter

LAOADAM

Joined Nov 21, 2018
862
hi Adam,
I don't have a Robot to try idea's.
The Sketch I posted in your IR thread should detect the IR.

Let's know how it goes.
E
Thanks.
Sure I'll report the result if I got any.

BTW. is it possible to use a 38KHz Infrared IR Transmitter module to do a encode sending and use a
38khz Infrared Receiver Module to do the decode?

ir11.JPG
 

ericgibbs

Joined Jan 29, 2010
18,766
hi Adam
BTW. is it possible to use a 38KHz Infrared IR Transmitter module to do a encode sending and use a 38khz Infrared Receiver Module to do the decode?

Do you have a datasheet for a 38KHz Infrared IR Transmitter module.?

E
 
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Thread Starter

LAOADAM

Joined Nov 21, 2018
862
hi Adam
BTW. is it possible to use a 38KHz Infrared IR Transmitter module to do a encode sending and use a 38khz Infrared Receiver Module to do the decode?

Do you have a datasheet for a 38KHz Infrared IR Transmitter module.?

E
Thanks.
I didn't find exactly the datesheet for the module above, this one maybe similar?
 

Attachments

ericgibbs

Joined Jan 29, 2010
18,766
hi Adam,
I have that d/s for a RX module, but I have not seen a dedicated 38kHz IR TX module d/s.
The TX PCB image you posted in post #7 of the Emitter will accept a 38kHz drive square wave for 38kHz IR LED
I would consider using a 7555 timer set for 38kHz to drive that IR emitter and just Gate the 555 On/Off with an out pin from the Arduino.
E
BTW: I have those modules post #7 and a TSOP38 on the bench, so I can check your Sketches.
 

Ya’akov

Joined Jan 27, 2019
9,069
hi Adam,
I have that d/s for a RX module, but I have not seen a dedicated 38kHz IR TX module d/s.
The TX PCB image you posted in post #7 of the Emitter will accept a 38kHz drive square wave for 38kHz IR LED
I would consider using a 7555 timer set for 38kHz to drive that IR emitter and just Gate the 555 On/Off with an out pin from the Arduino.
E
BTW: I have those modules post #7 and a TSOP38 on the bench, so I can check your Sketches.
Eric, are you familiar with irremote.h? That seems to be the library the board is targeting. The library provides the transmitter modulation, as far as I can tell: https://github.com/Arduino-IRremote/Arduino-IRremote

Note the comment in the 8MHz AVR only doing 30KHz, and two others.
 

Thread Starter

LAOADAM

Joined Nov 21, 2018
862
I have a question here, if I use two IR receivers to receive one IR emitter, can I let the two receiver start to receive at the same time? or do I have to start the receiver alternately?
Thanks.
 

ericgibbs

Joined Jan 29, 2010
18,766
hi Adam.
How will the two IR TSOP detectors be connected on their outputs.?
Why do you need the two detectors.?

It would help if you posted the project design spec.
E
 

Dave Lowther

Joined Sep 8, 2016
224
It's very simple to use an Arduino to deocde the output from remote controls using this library:
1645179955010.png
I used the receive example sketch that comes with the library and the following hardware:
1645180162822.png
Using TSOP4838. Pin out (as shown in above photo with dome facing and pins down) left to right 1-Output, 2-Gnd, 3-Vcc. The output is connected to Arduino pin 2 using the purple flying lead.

After seeing what the Arduino decodes on the serial monitor for various remote key presses then it's also easy to use those values to get the Arduino to emulate those key presses.
 

ericgibbs

Joined Jan 29, 2010
18,766
hi Dave,
I have already done a number of working projects using Arduino's and TSOP's, encoding/decoding etc.

I really want to know how Adam is planning to use TSOP's in his project.:)

E
 

Dave Lowther

Joined Sep 8, 2016
224
hi Dave,
I have already done a number of working projects using Arduino's and TSOP's, encoding/decoding etc.

I really want to know how Adam is planning to use TSOP's in his project.:)
Sorry. I saw a couple of mentions of Arduino and thought it might be helpful to show how simple the wiring is for a receiver. The transmitter is no more complicated, just an external IR LED and a resistor. I'll keep quiet and just watch from now on.
 

Thread Starter

LAOADAM

Joined Nov 21, 2018
862
It's very simple to use an Arduino to deocde the output from remote controls using this library:
View attachment 260966
I used the receive example sketch that comes with the library and the following hardware:
View attachment 260967
Using TSOP4838. Pin out (as shown in above photo with dome facing and pins down) left to right 1-Output, 2-Gnd, 3-Vcc. The output is connected to Arduino pin 2 using the purple flying lead.

After seeing what the Arduino decodes on the serial monitor for various remote key presses then it's also easy to use those values to get the Arduino to emulate those key presses.
Thanks.
 
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