Archives | July 2012

Continued debugging has produced another dozen fixes for the HVR-950q. Most of these are low-probability failure conditions (race conditions, etc). However take a bunch of 1/1000 chance items together and you're likely to hit one of them once in a while... A couple of noteworthy changes: Firmware load time has been sped up to 2.9 seconds (down from 8-10 seconds). This should eliminate the need for MythTV users to specify the "no_poweoff" xc5000 modprobe since it will now load fast enough to avoid a mythfrontend timeout. Fix a case where the xc5000 tuner enters a failure state and all subsequent...

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If you've ever had to poke at a DVB driver under Linux, you'll notice that the configuration for the demodulator and tuner refer to an "IF". For example, with the xc5000 driver, there is a mandatory parameter called "if_khz" which has to be provided when the driver is initialized. What is an IF, and what role does it play in making tuners work under Linux? "IF" stands for "intermediate frequency". To understand the role of the IF, we need to first take a step back and understand what a tuner actually does. A tuner takes a slice of the available spectrum coming in on the antenna, and outputs...

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