How to connecting tx rx arduino duemilanove

Hello, im new with arduino controller, just try to learn more in this controller. I just try few example on arduino alpha to make i understand better on arduino. For now i try to read honda obd1 ecu data, but i cannot find enough information how to connect the communication pin between the ecu and arduino diemilanove.

Here the pin ref:

Honda ECU Arduino Pins
Pin1 Gnd Pin (any ground pin)
Pin2 Tx Pin0 Rx
Pin3 5V(Power) Not connected (N.C)
Pin4 Rx Pin1 Tx

It this right connection to read from adruino to other controller comunication port? Tx arduino will go to Rx other device and Rx arduino will connected to Tx other device. And connect Gnd arduino to Gnd other device. I just leave the not connect 5v pin. Please correct me if i wrong.

And any chance damaging my arduino if i connect wrong connection?

Play safe and interpose some resistors (4k7 might be a good value) in the signals? I quick google suggests 10bit (1 start, 1 stop) and 38400 baud, but that wasn't a "definitive" source!!!

KE7GKP:
Yes, typically the Tx goes to the Rx at the other end (and vice-versa).
Of course, you must have the baud rate, stop bits, etc also matching.

Can't' answer your questions about possible damage because we don't know what are the voltage levels the Honda ECU uses?
Arduino can be damaged by any signal > VCC (5V, or 3.3V for the low-power boards) You didn't mention which Arduino you are using so dunno whether you limit is 5V or 3.3V?

it same with obd0 & obd1 datalogging using moates.net extream hulog cable & driver setup:
baute rate : 384000
data bit : 8
parity : None
stop bit : 1

I'm using arduino diemilanove with 168P chip, and Honda ecu side using 12V and 5v, there some component using 12v power, and for the communication it using 5v max.

i just thinking should i connect 5v arduino to 5 v ecu or not?,

MarkT:
Play safe and interpose some resistors (4k7 might be a good value) in the signals? I quick google suggests 10bit (1 start, 1 stop) and 38400 baud, but that wasn't a "definitive" source!!!

datalogging setup will be same with ectram hulog hadware :

http://support.moates.net/2009/02/10/usb-driver-troubleshooting-101/