Wednesday, March 19, 2008

My USB-UIRT failed on me

Just when my wife was REALLY starting to take a liking to mythtv (she's been rejecting the mythbox for years, all the while desperately holding onto the TiVo), I suffered a tiny setback to my progress. I had to experience a hardware USB-UIRT died on me. Luckily my wife is pretty understanding of stuff like that, and I was able to get things back up and running quickly enough, so she really hardly noticed:

My previous IR experience

For several years, I had been using a IRA-3 serial port IR receiver from I was very pleased with the device, and it served me quite well. However, when I decided to rebuild my entire mythtv system late last year, I decided I had a few additional needs. One, I wanted something that could transmit as well as receive. Second, I wanted a USB device that I could use to wake the machine up from suspend-to-ram when I pressed the power button on the remote. After searching around, the USB-UIRT seemed to be the device that best suited my needs and had some happy users.

Unhappy with the USB-UIRT

My experiences with the device, however, had been less than satisfactory. First, there had been some code reverted in the latest kernels, and the device no longer functioned without patching and rebuilding a kernel driver. After spending a lot of time figuring that out, and then finally successfully getting it all working, the next release of the kernel seemed to fix the problem, so all of my work accomplished little. However, being that linux isn't an officially supported platform for the USB-UIRT, I could hardly blame the manufacturer (well...I guess I COULD blame them for not caring to support linux).

Once the device was up and running, my next task was to program the device. I immediately had trouble, as irrecord kept telling me there was an error reading the signal. After much trial and error, I was able to brute force my way through the errors and get it to record my lircd.conf file. By contrast, my IRA-3 worked perfectly every time in this regard.

Once that was working, the next thing I noticed was that the device was VERY finicky about the remote being pointed directly at it. If I pointed it just a tad too high, low, or to the side, it would only pick up the IR signal intermittently. A little more that that and it wouldn't see it at all. By contrast, with my IRA-3, I could point the remote at the ceiling, the opposite wall, or even stand in an adjacent room and it would still pick up the remote.

Next came the task of getting the device to wake the machine from suspend. I was able to program it with my remote's power button signal and get it to wake the machine successfully. However, I then ran into the discovery that, as soon lirc tried to use the USB-UIRT, the device's state would somehow get corrupted and it would no longer wake the machine up. I would have to physically unplug the device before it would wake the system again. Thus I had my choice of using it for lirc, or using it to wake the machine, but not both.

The final straw came this weekend. The USB-UIRT was working perfectly. I left the room, came back 30 minutes later, and the red light was stuck on. The device was no longer responding to IR signals, and nothing could get it to work again (rebooting or unplugging it didn't help). There were other posting of the same problem in the support forum, but no response was ever posted by the manufacturer. Now it looks like I'll need to send it back.

Final outcome

Overall, I was quite disappointed in the device. It's performance was inferior to the IRA-3 in almost every respect. The one aspect where the USB-UIRT actually didn't disappoint me was with the IR emitter. I was able to get the IR emitter working successfully with little effort. However, I never got a chance to actually implement that aspect of it on my system, so I never got to put it through its paces.

For now, luckily my IRA-3 was still sitting around, unused and functional. I was able reconfigure my myth frontend (drivers, config files, and scripts) and get it working in relatively short order. My wife barely noticed downtime.

The only downside to the IRA-3...I've only got one serial port, and now I'm using it. I was just about set to start controlling my TV via the RS-232 serial port, but now I have to put that plan on hold. I've ordered a PCI serial port card and am waiting for it to arrive before I can continue. I've also still got to find a solution for waking the machine from suspend, and I may need to come up with another device to do the IR transmit functionality.

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