Hi there, Am Freitag, 7. Januar 2005 21:14 schrieb Aurelien Jarno: > > 111111111111111111111111111111111111111111111111111111111 > > Detection of the DS1621 in sensors-detect is broken. According to the > > data sheet of the DS1621, one bit of the configuration register is always > > 1 and another always 0. This is simply not true, if the chip is not > > properly initialized. I suggest the following replacement for sub > > ds1621_detect in sensors-detect > > That sounds me strange. I am using a ds1621 plugged onto my parallel > port I2C interface and the module is always loaded at boot. I am using > this for more than 4 years (the chip is dated 0022, ie year 2000 week > 22). Well, may be strange - but that's fact. The data sheet does not have a single line indicating that the two "fixed" bits may be overwritten - and yet, something does this. >> # subroutine modified by Peter A. Henning >> # Old version checks, if Bit 3 is set and Bit 2 is clear. >> # ==> THIS IS NOT ALWAYS TRUE > ># The DS1621 will however aways have a config like 0x????1??? > If the chip is not correctly initialised, there is also some chances > that this is not always true. Could be, but with three different DS162 chips I found not a single case where the 0x????1??? was not true. > Moreover it will be weakening the > detection which is already not very strong. That could make some chips > to be falsely detected as ds1621. Agreed. But worse is the case where a positively identified DS1621 i snot recognized as such - and the detection gets stronger than in the old code when the temperature is properly identified. > > The better solution would be to understand why your chip does not > conform to the datasheet. Agreed. But I have three chips on the same bus now, and they all behave the same > > Are you using a ds1621 chip or a compatible one (ds1625, ds1629, ds1721 > or something like that)?, DS1621, stamped 0445B4 265AE Three chips, bought December 2004 > Are you sure they is no interference between your asb100 chip and your > ds162b1? Of course not. But I deem it unlikely to have the asb interfering with the three different chips (sitting at different addresses of course) in the same way > AFAIK, the VT8235 only has support for smbus and not i2c. The minor > differences in the protocol (mainly timing protocol), may cause bus > lockup. Do you think it may correspond to what you are observing? > Asus advertizes the board to have an SMBus interface. And yet, Dallas does not say anything of SMBus and s quoted as being I2C compatible. > Or maybe the new Dalls chips are buggy... Do you want to test one of mine ? Best regards -- Peter Henning ----------------------------------------------PGP 0x5CDC14A1 ------- | Prof.Dr.Peter A.Henning | | European E-Learning Award EureleA | http://www.eurelea.org | | Director MediaLab | Computer Science, Karlsruhe University of Applied Sciences | http://medialab.fh-karlsruhe.de/ |-------------------------------------------------------------------
