Want to make a 14 channel transmitter and reciever any idea's

I want this project to be rf with at least 75' feet range.

Want to use a PIC

How would I go about doing this

Any idea's.

__________________
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Use licence free radio modules, these are easily (and cheaply) available, and some have ranges far exceeding 75 feet.

You need to provide some kind of transmission coding, Manchester is the one usually used - you can also get the modules with RS232 to Manchester coding included, these would make it a LOT! simpler. There doesn't seem to be a great deal of Manchester source code around, although there are a few examples!.

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You have to be a bit more specific, like what type of radio modules? because a radio module could be anything from a stereo to a rc car got to be more specific. Also website's that would sell this type of product or where I might find resource's to help me make it.

__________________
Robotics is heaven in my book.

 

The specific part was 'licence free', the exact spec varies from country to country, and you may have more than one allocated band - commonly they are around 433MHz.

For a specific example try http://www.rfsolutions.co.uk/acatalo...o_Modules.html, but any decent component supplier will stock something similar, there are many manufacturers of them.

__________________
PIC programmer software, and PIC Tutorials at:
http://www.winpicprog.co.uk

 

You think I would be able to get 14 channels?

__________________
Robotics is heaven in my book.

 

14 different channels as in frequencies under a licence free scheme, no way. I wouldn't go digging around for that many different frequency TX/RX.

What exactly is it that you are trying to control??
How fast does the response of the channels have to be??
What Nigel is suggesting is that you take a PIC with 14 inputs, convert it into a serial data stream and send it out of a single pin of a chip.

It's a bit like morse code, you have one flashlight and flash it in a sequence and the reciever interprets the information into 14 channels. There is only one transmitter (one flashlight).

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Exactly that is not what I wanted.

Also, what I am doing is controling a multi purpose robot which I could activate him to be Autonomous, and disactivate him to be RC. I would have functions like light's on/off, a vacum cleaner, a button to send him to his charging station, and also a joystick to control his dc motor's and elec.

A general robot.

Also I would you the 14 channels for dc motors, vacum cleaners, relays and elec.

You get what I am saying

__________________
Robotics is heaven in my book.

 

Yes, and the method I suggested is EXACTLY what you want.

It's how remote control works, you send some kind of serial data, and the receiver decodes it. Standard radio control (as used for cars and planes) uses successive pulses of differing width to indicate the positions of the servos.

By using a digital serial data stream you can send analogue or digital information, and as many channels as you want.

__________________
PIC programmer software, and PIC Tutorials at:
http://www.winpicprog.co.uk

 

So you are saying that I could have a more then 14 channels.

would the website you gave me above, have transmitter/reciever modules that would give me 14 channels?

__________________
Robotics is heaven in my book.

 

No, it has modules which give you a 'radio link', what you do with it is up to you - but using those modules you could easily create a 14 channel (or more) radio control system.

Perhaps you might be confused about 'channels'?, to give an example - a model car uses a two channel radio system, one for speed (negative speed is backwards, positive is forwards), and the other for direction (left/right). A model plane usually uses 4 channels, throttle, rudder, elevator, ailerons.

Your request for 14 channels implies you want to control 14 functions of a robot from a single control.

__________________
PIC programmer software, and PIC Tutorials at:
http://www.winpicprog.co.uk

 

There are two answers.

#1. Follow Nigels method (recommended)
#2. Use 14 different frequencies.

I would go against #2 because there is a 50% chance you will need a license to use the transmitters, PLUS, there may be more circuitry involved and the chances of error are much higher.

Use method 1.

All you need is only one frequency to work with. The key here is the data.

Let's say you have all sorts of things to control. Now if we labeled them like so:

1 = turn vacuum on
2 = turn vacuum off
3 = go forward
4 = go backward
5 = whatever else....
...
...

what you can do is assign each command to any binary number of your choosing, but make sure none of the commands use the same number.

You first need to count every single command the robot needs to impose, and determine how many things it can do at the same time. If it seems like every command can be done at the same time, then use the bits as switches. Here's an example:

Say you have 10 commands, and the robot must do nothing. You send this:

0000000000

Say that command 1 and command 3 must be done. Send this:

0000000101

You treat the bits as switches. When the bit is 1, the command is active.

These bits are what you transmit, and the robot decodes them.

 

Hi!!
Two weeks ago I had this problem.
I used regular RF module.But for realize control 14 channals was used encoder and decoder from HOLTEK.Works very good.If you need more information let me know.

 

Boris wrote:
Hi!!
Two weeks ago I had this problem.
I used regular RF module.But for realize control 14 channals was used encoder and decoder from HOLTEK.Works very good.If you need more information let me know.

Cool, does it do some of the function's I want like dc motor control, relay control and elec.

Also do you have the website where you got this stuff, and did it give you good range?

Is this all that you used in your project

1.Rf module
2.Encoder
3.Decoder

is there anything else that you might of forgot?

Which microcontroller did you use?

__________________
Robotics is heaven in my book.

 

Hi!!!
I use RF moduls TXM-433-LC and RXM-433-LC-S.All information you can take on www.linxtechnologies.com
Information about Encoder and Decoder you can finde from www.holtek.com
I use encoder-HT640 and decoder HT648L.But I made small modification for control more than 15 comands,because those IC's has a 8 inputs and outputs.
If you need informatoion about modification give me your e-mail and I'll send all schematics. Becuse I can not post all my schematics in this window.
To control encoder and decoder you don't need use microcontroller.
I use microcontroler PARALLAX (PIC) for another functions.

 

My e-mail is on the e-mail icon right by profile,www,e-mail

__________________
Robotics is heaven in my book.