Thursday, August 14, 2008

More Pinnacle PCTV HD frustrations...

Continued to debug my xc5000/dib0700 i2c problem today. Didn't hear back from Patrick Boettcher on the i2c problem I found, so I didn't even bring up the more intermittent failure I am now trying to debug.

Confirmed that the xc5000 firmware provided in Steven Toth's driver is 100% identical to the code being uploaded via the windows driver (binary diff'd). I really wish I knew what it meant when i2c write requests returned a status of "-32". Continues to piss me off since if I had the datasheet I wouldn't be fumbling around and wasting my day off trying to reverse engineer the device behavior.

To add the the weirdness, it turns out I don't see the xc5000 tuner being set to the target frequency **ANYWHERE** in the Windows SniffUSB trace. Yeah, how the hell does the tuner know what channel to go to if the message isn't in the trace? It has me seriously worried that there might be a bug in the sniffer tool. Either that, or there is some other command for adjusting the tuner, perhaps through the demodulator. I have traced every single i2c call made to address 0x64, and all I am getting in the trace are the commands to load the firmware. I am not seeing any register reads or writes at all.

I also uncovered a bug in mrec's usbreplay tool, which was causing it to not be able to parse my traces. It turns up the offsets into the lines are all hard-coded, and if you have a timestamp large enough to add an extra digit, the file cannot be parsed. I can fix it but it was just faster for me to pass the capture file through sed and truncate off the leading digit.

Right before I left for vacation, Christoph contacted me about the progress he made on his KDE4 port of Kaffeine, and he wants me to debug the ATSC scanning. I want to do it, but I've just got too many projects in the hopper. And in this case, I would actually have to setup a Linux box with KDE4, whereas right now I'm running a hacked up version of KDE 3.5.

There just aren't enough hours in the day. It's a little frustrating to have the entire day off from work, and in the end I didn't get *anything* working.

I guess that's not completely true. I did get the the new hard drive installed in my MacBook, and got Leopard installed so I'm back up and running.

I wonder if anybody I know has a digital oscilloscope with enough buffer to do i2c capture... Or better yet, an actual i2c bus analyzer. They're 300 bucks, which is cheap for lab equipment, but way outside my budget...