[mythtv-users] FYI: harmony 650 37.99 @ costco (instant 17 rebate)

Mike Perkins mikep at randomtraveller.org.uk
Wed Nov 30 11:07:36 UTC 2011

On 29/11/11 20:05, Kris B. wrote:
> On Tuesday, November 29, 2011 11:11 AM, "Gabe Rubin"
> <gaberubin at gmail.com>  wrote:
>> How would the remote know which device is on or off and which power on
>> codes to resend (which is typically the same as a power off code)?
>> I can't imagine how else this could be accomplished by a universal
>> remote (other than individually turning on the receiver by switching
>> the remote to device mode or using the help functionality -- both
>> options of the remote).  Without the receiver and tv giving the remote
>> some feedback, which afaik, is impossible, there is no other way to do
>> this.
> Most devices have "hidden" remote control codes - Your TV remote has
> Power, which is a toggle on and off, but there are usually hidden codes
> for Power On, pressing it once or twice or fifty times only turns the TV
> on, never off.  The Harmony depends on that type of code in this
> circumstance.  Same with input, you might have a button that cycles, but
> there is a "hidden" button/code Input 1 and the Harmony uses that.
> Pretty cool, actually, because I hit "Watch a DVD" and it will send a
> Power On TV command (which will either do nothing if I already have the
> TV on, or actually turn on the TV), change to the specific input on my
> TV, then power up the DVD player.  When I switch to watch my computer,
> it will Power Off the DVD player, send the TV On command again (if it
> forgot that I had the TV on, like if I drop and accidentally reset the
> remote), switch to the correct input, wake the computer with a keypress
> (program shift button to do this so it doesn't lose your spot if you had
> already had the computer on), and go about its' business.
> However, if I miss aim and the device is finicky (like one that doesn't
> have a power on only command, just a powe cycle) you can get in these
> loops where you have to intervene or switch between devices to get back
> on track.  Rare, but annoying to explain to the wife :)
I think that the remote works a little simpler than you describe. I have a 
Harmony 600 remote which *almost* works the way I want it, and it is possible 
that other Harmony remotes may work differently, YMMV.

I believe that the Harmony keeps an internal state for each of the programmed 
devices, so that it 'knows' when something is supposed to be on or off. This is 
why when your TV is already on and you switch inputs it doesn't send another 
power-toggle command to the TV but only sends them to the other devices as required.

So, if a cushion gets in the way and a command gets missed the remote "thinks" 
everything has worked and you therefore need to use the "Help" button to 
resynchronize it with reality. Although some devices may use hidden codes I 
don't think they all do.

I keep all the other remotes in a drawer out of sight. This means people aren't 
tempted to use them and confuse the 'system state' but it means I can get one 
out and fix any odd problems without going through the Harmony's help cycle. 
Sometimes it's just quicker that way.


Mike Perkins

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