A loopback test with a single wire connecting the port's Rx & Tx lines is always one of the first tests I do when diagnosing serial comm's issues. If you aren't using a modem, I suggest also removing all of the modem init strings from your minicom
configuration. Is your problem that minicom
doesn't automatically go online, or that it simply will not go online at all?
Another useful tool (requires X) for setting up serial comm's is serlook
. It is less useful for the level you're working with right now, but comes into play where you are actually transferring data between hosts or host & device.