On Mon, Sep 26, 2005 NooneImportant wrote: > On 9/26/05, Johannes Stezenbach js-at-linuxtv.org > > Could you please test if the SAA7146_I2C_SHORT_DELAY flag > > fixes the dishnetwork emulation for you stv0299 budget card? > > (Because I don't see why set_voltage() should be slower on > > stv0299 than on other frontends.) > > I don't have a budget card in my system right now, so I can't test it > at the moment. > As I recall the problem was these two commands at the top of > stv0299_set_voltage: > reg0x08 = stv0299_readreg (state, 0x08); > reg0x0c = stv0299_readreg (state, 0x0c); > > The time it took for them to return was often longer than 8ms on my > Nova-S card (but not on my Nexus-S). Is this something that > SAA7146_I2C_SHORT_DELAY could fix? I'll try it again when I get a > chance though. Yes, these two i2c messages whould take less than 8ms with SAA7146_I2C_SHORT_DELAY. > I should mention that even with the tuned code in stv0299.c, my budget > card only manages to successfully control the switch 80% of the time. > The problem appears to be (from examining with an o-scope) that the > voltage control is just not very precise on that card (lots of noise > on the output as it switches compared to the Nexus-S, which is very > clean). I don't think there is anything that can be done about that > though. Hm, the card should be able two switch the voltage fast enough to generate a 22kHz signal... Johannes
