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DirecTV HR-21P Pro Receiver Control

I'm considering RS-232 vs. IR control and don't require feedback from the Rx. I've read the previous threads regarding sleep and lock up issues. Has DirecTV addressed these issues for the DB9 port or does anyone know if it still "sleeps" if using the USB adapter?

The IR port on the back of the unit looks like a 3.5mm stereo headphone jack and is labeled: tip - +5 out; 1st ring - data in; 2nd ring - ground. Seems I would use the 1st & 2nd rings for the 2-wire connection to an IR port on a NI-3100, is this correct? Any update or opinion will be appreciated.


  • ColzieColzie Senior Member Posts: 470
    I've done the Pro, but the only useful feedback is the current channel number. This is nice to have on the TP, but not very exciting. If we could get back the station name and program info, then I would say 232 is definitely the way to go.
  • DHawthorneDHawthorne Old Timer Posts: 4,584
    That's pretty much where I stand ... I spent a lot of time with the RS-232, and was very disappointed with the limited feedback. It's just easier to use IR until and if they expand the protocol somewhat. It doesn't even so much as tell you what tuner is active, and everything has to be queried.
  • TurnipTruckTurnipTruck Junior Member Posts: 1,485
    I use RS-232 with a USB adapter on an H20. I have had no issues with with lock-ups. The button presses are a bit more responsive with serial when compared to IR. I poll the receiver occasioanlly for channel number and signal quality.
  • dhill@cejh.com[email protected] Junior Member Posts: 2
    Thank you, I'll stick with IR. Now about that IR jack wiring question , , , ,
  • Adam GershonAdam Gershon Moderator Posts: 23
    I use the AMX DirectTV HR21 module to control two HR21's with the USB to serial adapter.
    The biggest value I have found to using serial control is for favorite channels. The instantaneous selection of a channel number is a far superior method, in particular if you are using the set top boxes for a distributed music system where there is no TV for on screen display. In addition this provides the ability to highlight which favorite channel is selected. The speed with which a channel is selected and the reliability make this a no brainer for me.

  • Chip MoodyChip Moody Junior Member Posts: 727
    You had it - IR signal to the ring, ground to the sleeve. If I'm reading correctly, you want to use an unmodified IR driver for that - I.E., don't strip the carrier or invert the signal...

    - Chip

    Thank you, I'll stick with IR. Now about that IR jack wiring question , , , ,
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