Software Protocol for IR Tx-Rx pair

[Golden Electronics]

I want to design circuitry in which we use 12 IR Rx-TX pair which make matrix. Now when any beam cut than alarm on. Can u suggest which protocol use for Tx & also at Rx such that i know exact location of sensor. Is RC5 is okay or something other

 

[betwixt]

I'm not sure you need any proocol at all for that, it sounds to be more like a simple case of detecting the presence of a beam or not.
When you say 'matrix' do you mean a grid (maybe 3 sensors long and 4 sensors wide) and you want to know where in the grid an object is when it breaks an IR beam?

If that is what you want, a multiplexing scheme would work better, just activate each IR LED and sensor in turn and see if light passed between them.

Brian.

 

[Golden Electronics]

Is same method use in Safety curtain system also......

 

[betwixt]

I understand. RC5 and similar protocols are methods of sending data by light beam. What you need here is something simpler. All you have to do is flash each IR LED in sequence to it's respective sensor and see if the light beam arrived. If you arrange the beams in a matrix you can find the location of the obstruction by noting which 'X' beam was broken and which 'Y' beam was broken.

Brian.

 

[Golden Electronics]

Actually my placement is matrix but Tx & Rx section away from each other around 2 mtr. So I have no idea when tx active say TX3 active than i require to check is RX3 is active or not like this

 

[FvM]

In this case, the TX channels have send to send unique codes, sequentially.

 

[Golden Electronics]

thanks betwixt & Fvm I will try & inform if any

 

[betwixt]

Or send no codes at all.
Is it possible to simply send constant IR beams and see which pair doesn't arrive at the receiver? It really depends on the environment it has to work in.

Brian.

 

[123jack]

If you use plain pulses you will reduce power consumption - if using batteries that may be useful -
otherwise I'd agree with all the above
Just read your recievers to capture a signal and count the time between "hits" -
- if one is not seen - say every 100ms - you might assume a break
Using a protocol is really overkill that will involve you in more work than you need.
On the other hand if you suspect serious attempts to breach security a more comprehensive
signal would be appropriate - but don't use anything standard in such a case.