Before I try this.. I just got a Harmony 650 for my wife, I would of gotten a 700 or higher remote if I thought that cost of the added device was worth it. (I am use to remotes with more than five devices like the 880 and the 'China Clone 688' {From eBay, which at time of purchase I did not know it was not a true Logitech/Harmony device, but Logitech allows this device to access their data base luckily}.)

But I find that I am one device short.. my HD-DVD player ..as it will play DVD+R home made DVD where my new BluRay player will not.. but back on topic..

My TV is a Toshiba, can I add by learning the key presses for the HD-DVD to the TV's library of commands??

Then set-up a generic setting to watch HD-DVD to have my receiver and TV switch to the correct inputs / volume control?

:David

(PS: or is there any way to combine two DirecTV DVR's as a single device and just change the device code in the remote via macro?)

(I was able to do a like combine device function with JP1 remotes, in the past!)

1) Yes, you can teach any command from any device to any other device (including teaching commands from an alternate dataset). Just make sure you use the correct OEM remote configured for the desired device code (if applicable). Also make sure you use appropriate command names. I recommend you precede the name with the intended device like DVDPlay, else it will become very confusing to both you and the database police.

2) No, you can not combine two DirecTV DVR's as a single device, but you can teach it commands from its alternate dataset (see 1 above).