Using 433Mhz Tx & Rx with picaxe to operate toy car

[Gaetano]

Hello All

I am trying to help a student with a remote control project where they will use the 433 Tx & Rx to operate the vehicle. I do not know enough about the 433Mhz Tx & Rx. I wonder if anyone could help me in relation to, how are the TX & Rx connected to the 08M picaxe? And also does the code operate in the same way that it would if you where programming a vehicle directly? Thank you for any help that is provided. Gaetano

 

[westaust55]

What you propose should be possible.

To enable folks here to better help you, can you please provide some further details:

1. Which 433MHz modules are you intending to use. Keymark from Jaycar, HopeRF types, or other (give a link to those applicable)

2. Some details on exactly how you intend the control to work. Certainly passing a byte or two of data between two PICAXE chips via 433MVhz is very easy.


Also, do a search on this forum. Several including myself have posts covering preambles. pauses and data for the simpler systems.
I have used the Keymark modules transfering 3 or 4 bytes at a time.

 

[Dippy]

Agree with westy.

Have you done ANY research into selcting an RF module?
Some are dumb, some are a bit smarter.
Dumb ones will require you to do some more coding a mentioned by Westy above.
The smarter ones make life easier but a tad more expensive.
Will you be doing this on the cheap or will your budget stretch to twenty quid?

A Westy has said, this has been covered in DETAIL many, many times.
I'm sure you spend half an hour searching on this Forum you will uncover a pile of info.

What is your skill level with electronics and coding?

Searching on "preamble" may filter out a lot of the waffle.

 

[moxhamj]

I did this a few years ago. There was a problem. I can't remember exactly what it was, but I think it was to do with the 08M running a servo and then going off and running a serin from time to time. I think the servos didn't like that. Maybe there is a solution to that now, eg some of the newer picaxes.

It did work in the end, but not quite as well as I would have liked. Hmm - worth breadboarding before soldering would be my suggestion.

 

[westaust55]

I did this a few years ago. There was a problem. I can't remember exactly what it was, but I think it was to do with the 08M running a servo and then going off and running a serin from time to time. I think the servos didn't like that. Maybe there is a solution to that now, eg some of the newer picaxes.

It did work in the end, but not quite as well as I would have liked. Hmm - worth breadboarding before soldering would be my suggestion.

Yes the X1 and X2 parts have a timeout function on the SERIN command.
Maybe use two 08M's - one driving servo's with some tighter comms with handshake (ie when an input is high then do a serin) from the other to send values across and second to accept data form 433MHz radio link