[mythtv-users] USB->Serial for controlling DirecTV boxes

[Brad DerManouelian]

On Sep 23, 2008, at 8:44 AM, David George wrote:

> On 9/23/2008 9:33 AM, Brad DerManouelian wrote:
>> On Sep 23, 2008, at 5:51 AM, Ken Mandelberg wrote:
>>
>>
>>> A related topic:
>>>
>>> I have a need to control an HR21 DirecTV DVR, independent of Myth.
>>> This
>>> DVR is doing some VLC streaming. Is there any standalone
>>> hardware/software for this? The hardware connection could be
>>> HR21-USB<>PC-USB or HR21-USB<>PC-Serial. (I presume there is no  
>>> way to
>>> the HR21 with the HR21 ethernet).
>>>
>>
>> Hook it up the same way you would when using myth. The "USB" port on
>> the box only looks like a USB port, but it's actually a serial port,
>> so you still need to go HR21->USB to Serial->Null Modem->PC-Serial.
>>
>
> It is a USB port otherwise it would not require a PL2303 USB to RS-232
> converter chip :-)
>
> Likely they have written the driver to only support the PL2303 RS-232
> converter chip for the port.  Maybe in the future Directv will  
> release a
> firmware update that will support additional USB to RS-232 converter
> chips (not going to hold my breath though).

That's nit-picky. The point is that you cannot just plug in a USB  
cable and use it to communicate with the box like the OP was asking.  
It can only use serial communications.