Capturing the channel numbers for hot swap to that channel?

I have a 3 TV Setup (1 Main Screen with 2 sub screens above it) on my Home Theater wall all running their own independent Direct TV Box (Model H20). I also have the Harmony 880 (but am considering the 890).


I'm looking to create a macro that will allow me to quickly change the channel from

one of the sub screens to the main screen with the hit of 1 button. I believe this

would require me to:

1. Capture the channel number of the sub screen

2. Enter that number into the macro

3. Etc.


Does anyone know how to do #1?


Thanks!