Konstantin Dimitrov wrote: > hello All, > > the only place that i can find where I2C bus bit rate is set for the > budget-ci driver is in: > > http://jusst.de/hg/multiproto/file/096a44e6732a/linux/drivers/media/dvb/ttpci/budget-core.c > > line 506: > > saa7146_i2c_adapter_prepare(dev, &budget->i2c_adap, > SAA7146_I2C_BUS_BIT_RATE_120); > > with that setting i got 16 locks out of 20 tries on Astra 19.2E, 11538V > > when i change "SAA7146_I2C_BUS_BIT_RATE_120" to > "SAA7146_I2C_BUS_BIT_RATE_240", i.e. decrease the I2C bus bit rate > then i got only 3 locks out of 20 tries on the same transponder > > when i change "SAA7146_I2C_BUS_BIT_RATE_120" to > "SAA7146_I2C_BUS_BIT_RATE_80", i.e. increase the the I2C bus bit rate > then i got 0 locks out of 20 tries on the same transponder > > as far as i know current I2C ICs can work at any I2C bus bit rate up > to 400kHz and The STB0899 can go up till 4MBps! Normally the private repeaters can go up till 66 kHz or 100 kHz at a maximum on many demods, but on the STB0899, behind the demodulator you have still 400k transfer! > > SAA7146_I2C_BUS_BIT_RATE_80 ~= 400 kHz > SAA7146_I2C_BUS_BIT_RATE_120 ~= 275 kHz > SAA7146_I2C_BUS_BIT_RATE_240 ~= 135 kHz > > so why STB0899 can't lock at any of these I2C bus bit rates ? There are many things to be considered for the STB0899, it is very delicate according to STM, even some small things can cause allergy to it. But when you have a properly working driver, it shows it's true colours in performance. When you are racing it to the limits, everything has to be perfect there, not much of tolerances allowed in such cases. Manu _______________________________________________ linux-dvb mailing list linux-dvb@xxxxxxxxxxx http://www.linuxtv.org/cgi-bin/mailman/listinfo/linux-dvb
