halcaponey
Posts: 1
Joined: Wed Feb 18, 2015 9:07 pm

GPIO, serial port, and radio transceiver

Wed Feb 18, 2015 9:39 pm

Hi everyone.

I've a raspberry pi model B for about a year now, I'm pretty happy with it, and I've got a big project for it : I want to turn it into a drone (quadcopter).

I'm actually on a research phase, I've found a tranceiver that could feet my need : https://www.tindie.com/products/DORJI_C ... drf1278dm/
documentation : http://www.dorji.com/docs/data/DRF1278DM.pdf

What I'd like to do is (with two of those) connect one to my pc through a serial port, and the other to my Pi through the GPIO.
But i don't know if that'll work.

From what i understood the data send to one on RXD pin 4, comes out on TXD pin 5, can anybody confirm that ?

Also connecting the transceiver to the GPIO sounds easy : ground, +5V, and a pin to read the transmitted data, connection through the serial port doesn't, from what I've read there is a ground, 2 port for transmitting data (witch one should I use), and no +5v (the voltage varies from +12/+3v to -3/-12v ???)

Is what I want to do possible ?
And how do I connect the transceiver to my PC with a serial port ?

appconwireless
Posts: 7
Joined: Sat Sep 20, 2014 5:23 am

Re: GPIO, serial port, and radio transceiver

Tue Mar 31, 2015 5:17 pm

This module is USART port. If it integrate with Raspberry Pi, USART port is the only choice in the process for data input or output
GPIO port is used as the monitoring serial port. And enable the module.
About connecting with PC, the module can be converted via USB adaptor for USART to USB invertor.
We suggest a more effcient module with iron shield, which have more anti-jamming ability. Pls check this link:
http://www.appconwireless.com/PRODUCTS/ ... g=en&id=21

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MarkHaysHarris777
Posts: 1820
Joined: Mon Mar 23, 2015 7:39 am
Location: Rochester, MN
Contact: Website

Re: GPIO, serial port, and radio transceiver

Tue Mar 31, 2015 7:34 pm

:(
... not a good idea.

1) RPi uses too much power
2) RPi is too heavy
3) RPi uses wrong voltage(s)
4) RPi (headless) is not the right MCU...

I would use an Arduino Uno on first attempt, then move up to the Mega, or Due (careful with the Due because it has the same problem with voltages 3v3.

The best MCU for the quadcopter is an Intel Edison (but, its a grown-ups board for sure). Its small, almost no weight, uses 1.8v logic (so be careful, needs level shifters) and is powerful.

The RPi is a great controller, don't get me wrong, just not for flight (how large will the quadcopter be?)
marcus
:ugeek:

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DougieLawson
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Location: A small cave in deepest darkest Basingstoke, UK
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Re: GPIO, serial port, and radio transceiver

Tue Mar 31, 2015 7:48 pm

So you think the A+ @ 23 grams is too heavy ... hmm.
Note: Any requirement to use a crystal ball or mind reading will result in me ignoring your question.

Criticising any questions is banned on this forum.

Any DMs sent on Twitter will be answered next month.
All non-medical doctors are on my foes list.

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MarkHaysHarris777
Posts: 1820
Joined: Mon Mar 23, 2015 7:39 am
Location: Rochester, MN
Contact: Website

Re: GPIO, serial port, and radio transceiver

Tue Mar 31, 2015 8:06 pm

Its not the weight of the card that's the problem. Its the weight of the power supply. The RPi just uses too much power; the batts required to keep the thing in the air for very long would probably not get off the ground. On the other hand, batts that would get off the ground wouldn't last long!

;)
marcus
:ugeek:

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