Cortex to Cortex Communication by Digital I/O

Folks,

I did a little searching and, for the keywords I used, came up empty; so I’ll ask this, even though I’ll bet lunch that it has been asked and answered in the past.

I am considering using two VEX Cortex microcontrollers to control a single robot.

The simplest method for implementing (very) low data-rate communication between the two microcontrollers seems to be creating connections between the two microcontroller’s digital I/O ports.

I’m assuming that this can be done safely, and will permit sending on/off signals between the two microcontrollers, but I want to confirm that assumption before doing it.

So, is it OK to connection a Digital Out port on one Cortex micro to a Digital In port on another Cortex micro?

Will On/Off changes made at the transmitting Cortex’s Digital Out port be detected at the receiving Cortex’s Digital In port?

Will misconfiguring the connected ports (out-to-out, in-to-in) harm the microcontrollers?

Blake
PS: I know it is possible to connect the two microcontrollers using their Tx/Rx Serial I/O ports; but for the moment, I hope to bypass the added software complexity using them would introduce.