TLP434A... Bruce or anyone??

[xnihilo]

Hi.
Maybe bruce from Rentron will read this.

I need to have a pic16f684 output a byte wirelessly to a PIC16F690.
The first pic sends 8 bits (an ID) every 1ms. The other pic, when needed, checks if the signal is broadcasted and read the ID.
I was thinking of using a TLP434a with a RLP434 to communicate via RF.
The emiting pic does not need to modulate the bits like I would with an IR link, or does it?
I can just send pulses of specific length for "1" and shorter length for "0" and the stuff is sent over air at 433 MHz... Right?
Any help would be welcome.

[BobK]

Hi xnihilo,

If you go to Bruce's website, www.rentron.com, and look for "remote control schematics" you will find the information you need. The article there is how to change from IR to RF but the RF part is what you are looking for. There's a parts kit as well as a sample program to get you going.

BobK

[xnihilo]

Yes, I've read that already.
What is unclear is: do I have to modulate my output or can I simply send for example a 600 US positive pulse to the transmitter. Moreover, there is a rise time greater than 600 Us I think...

[Bruce]

You do not need to modulate data as you would with IR when using RF. The carrier ON/OFF
is controlled by the logic input on the RF transmitter.

With the transmitter data input at ground you suppress the carrier. When the data input is
logic 1 the carrier is ON. All you're really doing is turning the RF carrier ON/OFF by toggling
the transmitter data input.

On this transmitter you're controlling a SAW resonator that creates the RF carrier.

This project http://www.rentron.com/Stamp_RF.htm is one very simple example. And
Dave Houston has several more advanced examples here you can find with a search.

Have a look at this http://www.linxtechnologies.com/Documents/encdecdatastruct.pdf for
an example of what a commercial encoder IC data structure looks like.

[xnihilo]

Thank you for the info.

Regards.

Charles

[Kamikaze47]

I would recommend using a preamble before the data, and encode the data with manchester encoding. There are plenty of threads on these forums that talk about both of these things.