Confirmation of Signal received?

Hey Guys, I’ve got an HDMI matrix and I just figured out how to control it via rs232 serial. The problem is, sometimes the control signal doesn’t make it to the matrix (only if more than 1 action is being performed at a time).

whenever a command makes it through to the matrix it sends back a confirmation that the action took place.

for instance if I want to change output A to input 2 I would send the command: 2V1.
then I would receive a response that would look like : AV:02->01

So, what I’d like to do is have the command send then wait for the response for maybe 1 second and if I don’t receive the response, have it resend the command and wait for the response again.

Any Ideas on how to accomplish this?