I'd like to create an infrared circuit that can modulate at two different frequencies: 100 Hz and 200 HZ.
In my project, I'm utilizing an Arduino Nano. How do I decide which components to use to build this IR circuit?
The distance between the transmitter and the receiver must be no more than 6 meters.
Thank you very much.
Why?
It is odd that you want to use two harmonically related frequencies because you will not get good separation using harmonically related frequencies. So your receiver will respond to some extent to the one you don't want it to respond to. These are also low frequencies to use for modulation. It is normal to use frequencies in the 30 to 40KHz range.
Well you need an IR diode and a resistor.
However you only say you want to produce the send circuit. What is going to receive it? You need a tuned amplifier to distinguish one frequency from the other and there is no ready built circuits that will do that, so you will have to make your own. How good are you at analogue electronics?
That is an odd statement normally people specify a minimum range. So a range of 5mm would be fine as this is less than 6 meters?
I think you need to specify a whole lot more about this project. What is it going to be used for and what is your level of competence with electronics and programming?
It is done in software by changing the registers that control the PWM frequency.
As I said before
This lack of detail makes it impossible to give any help.
That is a whole can of worms, it leaves a lot more questions that needs answering. It is likely that you can't do this project like you want because it is too complex for you and have not thought it through.
You still haven't said why you need two modulation frequencies or what the range should be.
Did you read my last reply? If so you certainly show no sign that you understood what I was saying. Is this just a google translate generated question from your end? Maybe you would be better posting in a forum that is closer to your native language.
I will explain myself again.
I need to build a robot that have to drive from one place to another place. (The distance between the source and the destination should be Max 6 meters .
I'm using an IR transmitter and TSOP 322 receiver. The frequency that the receiver receive the signal from the transmitter is 38Khz.
But the requirement is to modulate this signal in 100hz or 200hz by using the PWM pins from the Arduino NANO.
The transmitter uses Arduino NANO and the receiver uses an Arduino MEGA .
I need help with develop the circuit and how to modulate the signal with the requirement that I wrote above.
Thank you very much.
If I calculate it in this way ,I see that the frequency is 200hz and not 100.
190(26microsec)=4.93 mill sec and it gives me 200 hz.
What is wrong which my way?
Thank you again.
Now its clear thank you ! ,you help me a lot.
I will use the Arduino Nano with the IR transmitter in the first side and I will put an receiver in the second part of my project.
Which circuit can I use in order to develop this part of the project using the PWM modulation?
However I think you are misunderstanding what modulation you need. The modulation is the 38KHz and will normally be provided by the PWM circuit. The 100 and 200Hz will be signals, not the modulation. Is it that you just want one of the two signals? If so I don't think that you demodulator will work with that. Take a deep look at the TSOP 322 data sheet.
Thank you for your answer.
One of the requirements in the project is to make sure that's the modulation frequency will be 100 HZ or 200 HZ (Switching without software ).Only manually into the circuit.
Do you think it's possible that's the receiver will receive the signal from the transmitter at the distance of max 5 meters?
Have you understood that correctly? In order to work with a TSOP 322 then the IR must be modulated at 30 to 57KHz, depending on the specific TSPP 322 you have. This is normally done by the PWM pin being set to generate a PWM signal at the modulation frequency. This is often called the carrier signal. If you do not do this the TSOP 322 will not respond to any pulsing of these bursts of frequency. With the bursts being known as the "signal". TSOP322 data sheet.
Anything on top of this is not modulation but the signal bytes you want to send. Maybe your teacher used the wrong words in setting the project?
That is just a nonsense. You need software to set up the PWM pin to the frequency you want, after that it just runs at that frequency constantly. Maybe that is what it means by the without software bit. However, to split the IR signal into bursts of data you need to use software.
Yes that is possible using a TSOP chip to receive the signal, but the signal must be modulated at the right frequency for the TSOP version you use, and if you use a modulation frequency at 100 or 200Hz the TSOP will receive nothing.
Also look at the data sheet for how long a signal burst can be. The maximum is 10mS. Any longer burst of signal will see the TSOP stop responding.
Note that the code in reply #17 will not produce the exact frequency, this is because the delay microseconds only has a resolution of 4 so a value of 13 will not give a delay of 13uS but only 10uS. A delay of 14 will give you 14uS.