Connecting two arduinos

Hey guys, im trying to simulate my project receiving commands from a different microcontroler through the TX and RX pins on the arduino. To do this i have another arduino connected to the computer and wire going from the TX on the computers arduino to the RX on my project, and the RX connecting to the TX. All I want is for the commands i type on the computer terminal to be relayed to my project through the TX and RX pins.

However I can't figure out how to get this to work.... Any sugestions? Thanks

Did you connect the two Arduinos grounds ?

You should:-)

Yeah good call on the grounds, however It still doesn't seem to be working... Should i pull the processor out of the relay microcontroller?

Maybe im not thinkin about this correctly... When I connect the project arduino to the computer using the usb, I use the terminal in the ide to send characters to the arduino. Can the TX and RX pins send the same characters?

sorry, noob bomb going down here, how exactly do u connect the two gnds? is it just a wire between any gnd pins on both arduinos… or is it a specific set of pins or what? :-?

As far as connecting the grounds, you can throw a wire between any of the ground pins. Basically everything that gets connected to the arduino needs to have the same ground. I still haven't been able to get a character through the RX pin though... Any ideas? Thanks

I'm not to pro at what ure doing, but maybe, have u found out if the arduino connected to the pc even gets the readings? perhaps its an issue with the very beginning of ure "system", like something u overlooked in the code...

Could you maybe give a diagram of the setup you have? When you say Tx and Rx, you don't mean the same Tx and Rx (pins zero and 1) that are talking to the host PC? Could you post your code? Do your baud rates match?

I did mean connecting the Tx and Rx pins (D0,D1) together. For some reason i was under the impression that when you remove the Atmega 168 chip from the arduino, it passes the info from the USB to the Tx and Rx pins. Now that I think about this some more im prolly not correct with that assumption.

Should I make a program on the pass through arduino to send out the characters it recieves through a couple of digital pins using software serial to the Tx and Rx pins of the other arduino?

I had a similar problem trying to debug an Xbee wireless connection. What I bet you will have to do is have the first Arduino receive the character from the IDE or terminal program and re-transmit that over a SoftwareSerial line (see this

This works great for sending to another device, but not so great for receiving because SoftwareSerial doesn’t have a receive buffer. Also make sure you’re matching the TX of one device to the RX of the other device instead of TX to TX and visa versa.

Do you have a sketch (like paper napkin style :)) of what you’re trying to do?