Sharp TV remote speed dial of sorts.

I discovered that when my TV is switched to input 4 (HDMI cable from the home theater) or, I am sure, any other input, in order to get back to the TV channels I only have to punch in the channel number or use one of the predefined colorful channel buttons (A,B,C,D). It remains to be checked if it is somehow possible to assign the HDMI input to one of those buttons.