If you are using the mythbox frontend in XBMC then yes you are using the Mythtv backend for your tuners and XBMC for your frontend. Word of advice, I would skip the IR blaster route. Just like with a remote, if the receiver doesn't catch the signal you could miss a show, or record something you don't want.
What I did was use firewire to control my set top box. I'm using the HD PVR (component) to record and firewire to change the channels. I get 100% accuracy this way. I have never missed a show. Plus it's cool to watch firewire change my channels for me. You don't have to go this route. However, if you did I can pretty much assure it will work like a champ. But you can try the IR blaster route. If you need help let me know I've been using Mythtv for quite a while. Mythtv's backend is second to none especially once you consider price.
Change channels via fireware? That sounds slick. Sadly, I don't have firewire on my mobo and no room for an expansion card (which I do have a firewire card) on my E350M1.
I setup my HTPC up last night to receive analog decrypted video from the cable box and into the component input (yellow RCA) of the HVR2250s expansion card (which is dangling out of a hole in the back of my case).
Problem:
I get all the way through setup in 7MC and then am face planted into a wall: IR HARDWARE NOT DETECTED. I try repeatedly to get this to work. I also try configuring the input as analog antenna to totally bypass the IR setup all together. But to no avail. IR is simply not detected.
Weird thing:
My HVR2250, which I made the mistake of purchasing off flea bay, has no IR plug on the main card, only on the expansion card with the component/s-video input.
Question:
What the hell do I do? I've try various utilities and drivers. I've try WinTV, Mythbox, 7MC.
Grrr.... I remember now why I gave up on my last HTPC project. I read so many posts of people just seamlessly setting their cards up, wish it was true for me.
Side question:
Seeing as how I may abandon this odd IR-less HVR2250, what tuner should I get in it's stead? Another HVR2250? Capture card? External tuner?
Thanks in advance!