gpio serial transmit distance

Moderators: adafruit_support_bill, adafruit

Forum rules
Talk about Adafruit Raspberry Pi® accessories! Please do not ask for Linux support, this is for Adafruit products only! For Raspberry Pi help please visit: http://www.raspberrypi.org/phpBB3/
Locked
User avatar
timwjkl
 
Posts: 56
Joined: Wed Jul 03, 2013 2:48 pm

gpio serial transmit distance

Post by timwjkl »

How far from the R pi can i have my arduino that is connected by GPIO and level shifter? Inches , feet , yards? I am only receiving data from arduino by design

User avatar
adafruit_support_rick
 
Posts: 35092
Joined: Tue Mar 15, 2011 11:42 am

Re: gpio serial transmit distance

Post by adafruit_support_rick »

That actually depends on the baud rate. At a few yards, you should be OK with lower rates. The level shifter will act as a repeater, so you can extend your range by putting it in the middle of the run.

User avatar
timwjkl
 
Posts: 56
Joined: Wed Jul 03, 2013 2:48 pm

Re: gpio serial transmit distance

Post by timwjkl »

I am using 9600 for the baud rate and and planing on using cat 5e cable unless something else will work better ? trying for 100~ feet

User avatar
timwjkl
 
Posts: 56
Joined: Wed Jul 03, 2013 2:48 pm

Re: gpio serial transmit distance

Post by timwjkl »

well So far i can transmit to at least 25 foot that is the longest piece of cat 5 I had at my desk. works fine also can program from my comp easy too with it hooked to a ftdi friend..

Anyone figured how to reprogram using a raspberry pi without being able to push the reset button?

I used the same cable to run serial gpio with the arduino too now to find my box of cable and check out the 100 foot :-)

User avatar
adafruit_support_mike
 
Posts: 67446
Joined: Thu Feb 11, 2010 2:51 pm

Re: gpio serial transmit distance

Post by adafruit_support_mike »

All you need is a low pulse on the reset pin.

If you have a free line in your CAT5, you could wire another switch to the RESET pin through the cable. You could also drive the wire from one of the RasPi's outputs.

User avatar
timwjkl
 
Posts: 56
Joined: Wed Jul 03, 2013 2:48 pm

Re: gpio serial transmit distance

Post by timwjkl »

I used the directions from the alamode http://baldwisdom.com/simplified-setup- ... pberry-pi/ and used RX,TX and gpio 18 on the pi and the arduino Rx Tx and reset with level shifter757 and a https://www.adafruit.com/products/72

With the extra cap at C6 it auto reset and programed the arduino without a reset button push.

I have been at this for a week and now i got out the 4X glasses and lo and behold i had the reset pins offset at the level shifter ( face palm)

User avatar
adafruit_support_mike
 
Posts: 67446
Joined: Thu Feb 11, 2010 2:51 pm

Re: gpio serial transmit distance

Post by adafruit_support_mike »

Been there. ;-)

I've miswired enough connections that I've learned to do two things: test each connection as it's made, and use a schematic with a checklist any time I inspect a circuit. It's *way* too easy to see what you think should be there instead of what's really there.

Locked
Forum rules
Talk about Adafruit Raspberry Pi® accessories! Please do not ask for Linux support, this is for Adafruit products only! For Raspberry Pi help please visit: http://www.raspberrypi.org/phpBB3/

Return to “Adafruit Raspberry Pi® accessories”