No the mistakes were mine as i somehow managed to attach it to the wrong parent serial port and it stopped the GUI in vera from working 
I had to log in, clean it and load a backup to get it back up again.
Ok, with the assistance of Javier, the code has now been formally pushed into the source control system, future copies should be grabbed from the link below:
http://code.mios.com/trac/mios_monoprice-hdmi-switch
sometime I’ll make a formal discussion thread for it, separate from this “DirecTV RS232 Plugin” thread we’re currently running in.
@strangely and I wrote a [Serial] driver for the DirecTV (HR20, HR21, etc) Series of DVR devices. We’re getting a source control space on code.mios.com shortly, but he’ll be posting the source files shortly (they’ll be attached to this thread as a short-term option), for anyone else that might be interested in having this.
For this to work you’ll need two USB Serial adapters and a Null modem adapter / Male-Male Gender changer. One Serial adapter must be Vera compatible and the other must be on the approved list of DirecTV supported USB adapters as listed in the document here:
http://www.sbcatest.com/DTV-MD-0058-DIRECTVSet-topInformationforInstallers-V2.2.pdf
If your Vera is nowhere near your DTV receiver then it its possible to also use a remote serial port such as the following WIZnet Ethernet device and the IPserial plugin:
http://www.sparkfun.com/commerce/product_info.php?products_id=9476
If your DTV receiver is already connected by Ethernet, then the second Ethernet port (if your model has this available) can be used to connect the WIZnet. The Wiznet will still need power but this can be taken from the second USB port on the receiver (if your model has this available).
Using SQremote, this is a great replacement for IR control and the response times are much better; this is especially noticeable when multiple key presses are used in succession, for example like FFDing at 4X speed.
Big thanks to @guessed for this, as I was really struggling to get it to work and he did most of the groundwork.
I’ve only tested this with a HR23-700 but it should be compatible with most of the HR2X series.
There maybe some controls missing, but as soon as I get some more time I’ll review it and add any missing ones. The Dash button is currently assigned to Misc1: “D” currently as there seems to be a bug that prevents using the “-” character.
The bug that @strangely refers to for the “-” key is:
http://bugs.micasaverde.com/view.php?id=1011
It indicates fixed, but I’m on a “high” Beta, and my release doesn’t have it, so we’ll have to wait for GA of that before we add the functionality. Given the API for DirecTV, there’s also possibility of getting more information “back” from that device, things like “what’s the current channel”, although not sure if people need that or not.
These are now checked into Source control over at:
http://code.mios.com/trac/mios_directv-media-control/browser/trunk
@Strangely, want to take a stab at the Wiki page for Description, and Setup?
Sure, If I can work it out; there seems to be no edit button 
I managed to reset my password at least anyway!
After you login to the Trac itself, you should now see a Button at the bottom of the Wiki page. I just granted you TRAC_ADMIN, which gives you a bit more than what you had before on that codeline.
Let me know if it doesn’t work, and I’ll try something else
OK that did it thanks!
I’ve updated it and its a bit of a blatant plagiarism and needs a bit more wok but anyway…
This Plugin has now been modified to permit both RS-232 and Ethernet based connections.
If the standard “ip” field is entered in MiOS Device config for this device, then it will use Ethernet instead of having to connect via an RS-232 adapter.
Subj on header post changed accordingly.
Hello:
Very much a noob, I just got my Vera2 in March. Lots to learn.
I installed the plugin for use with a HR-24 via ethernet. It seemed to go well except instead of channel information I get ‘Information unavailable’. I have the Whole Home DVR setup with a slave receiver attached.
Any ideas on how to troubleshoot?
Thanks!
John
Go into the system setup menu of the DVR, scroll to Whole-Home and make sure that under external device that everything is set to allow!
LOL you beat me to the punch!
You snooze you lose
Exactly the right answer. Thanks very much.
Good news!
Are you using it with SQremote also?
Strangely… With your plug in and SQRemote, are you able to see the channel being watched as it does in the control panel?
You mean can SQremote display the channel? If so then no I’m afraid not.
Is anyone controlling 2 Direct TV receivers with this plugin? I’m having trouble getting the 2nd instance installed and working correctly…any hints/tips?
Thanks!
Sorry to say, but I only have just one at the moment, but I may be swayed towards a HR34 when that comes along soon
Anyway, we might need a few more details to help:
*Which Vera version are you running? (there was a bug a while back where a second instance of the same plugin was broken)
*After you got the first instance working, how far do you get with the second one? I assume you can create the device again OK?
*How are you connected to the receiver? (IP or RS232)
*Which type of receivers do you have?
*If using IP to control them (rather than RS232), then can you successfully manage to control both from an iPad using the DirecTV app (if you have either)?
If you don’t have an iPad, then I also have a windows based app that I can send you, and you can test out control with, or we can probably send it some commands from a browser to check connectivity and response.
*Assuming you managed to get two plugins installed OK, have you tried to swap the IP’s between the plugins?