Connecting RC Receiver to MCU

MacTuxLin

Anyone know of a simpler way of input capture, maybe S.Bus, instead of connecting all the 8 channels from the receiver to prop pins? Is there a multiplexer input for PWM?

Thanks

SRLM

There's this:

http://store.3drobotics.com/products/ppm-encoder

MacTuxLin

SRLM wrote: »

There's this:

http://store.3drobotics.com/products/ppm-encoder

Thanks man.

MacTuxLin

BTW, if a ATmega could do this, couldn't the prop1 do this as well? Has anyone already done up an object for this? I'm in a mad rush project.......

Thanks.

Beau Schwabe

See post number 5 from this thread ... http://forums.parallax.com/showthread.php/102902-Propeller-as-PPM-encoder...

I was going the other direction to direct drive a Hitec "S" 72MHz PCM 6-Channel ULTRA Narrow Band RC transmitter.

With a little scoping you could find the same signal on the receiver module and decode that in a reverse process.

MacTuxLin

Thanks Beau, as always.

BTW, any chance of you being in Seattle in the last 2 weeks of Nov? If you are, we could catch-up for a drink.

Duane Degn

Some of the 2.4GHz receivers (I know this includes Spektrum gear) use a serial signal between the main receiver and the satellites. Several flight control boards use this single asynchronous serial connection to receive the control data from the receiver.

The transmitter uses a serial signal as input. I haven't hacked a receiver yet but I have hacked a transmitter and used a Propeller to translate input from a Wii Nunchuck into the signal expected by the transmitter. This allowed me to fly a RC helicopter one handed using a Nunchuck as a controller (the throttle and yaw used the accelerometer as input) (this doesn't make it any easier to fly).

I think a Propeller wouldn't have any trouble communicating via serial with the receiver unit. It's just a small matter of programming. This is one (of many) things on my Propeller todo list.

Phil Pilgrim (PhiPi)

You can use an 8-input OR gate to OR all the RC outputs together, with the output driving one Prop pin. The reason this works is that the receiver outputs pulses in sequence, one right after the other, with a small gap between them. At the end is a long delay between the last channel and the first channel that can be used for synchronization. Basically, this just undoes the time-demultiplexing that the receiver performs on the transmitted pulse stream.

-Phil

MacTuxLin

Thanks guys. I'll try these.