Hi, I have an external Hygrometer which stores temperature and humidity snapshots on the device and which can be read by a Windows software. I would like to write a Linux program to access the device and read the values. After analyzing the Windows software I found out that they are using a really "simple" I2C interface to the device, the plain serial port. Especially the status lines DTR (SCL), CTS (SDA Write), DSR (SDA Read). The chip that stores the values is an eeprom Atmel AT24C128/256 (?). After digging through the I2C/lm_sensors code/docs I found that much of the infrastructure for accessing eeproms has already been implemented in a modular way. Unfortunately I had to read about some restrictions, like that eeproms with more than 256Bytes (?) capacity are not supported and that there is not write support for eeproms. The device probably needs write support to reset the values in the ring-buffer. Because I'm new to I2C and kernel driver development I ask myself about the best approach to access the device, described above. There are currently too many unknown variables in my approach, so it would be kind if someone with good knowledge of the kernel I2C infrastructure could shortly explain what the best approach would be to write a driver for the device. Would it be possible to write a simple bus-driver, like the parport(-light) driver and use an extended version of the eeprom client driver to access the device? I would prefer this approach as it would allow me to use all the user-space I2C tools that access the I2C/lm_sensors APIs. But if the effort for extending the eeprom driver is high I need to investigate other possibilities as I would like to get something working really fast. Thanks in advance, Michael Michael Rumpf # Meissener Str. 4 # 71065 Sindelfingen # Germany Tel/Fax +49 7031 415883/884 WWW http://fsinfo.cs.uni-sb.de/~miru Misraet Dir voll Dein Tagesplan, sei Abends Dir als Trost bekraeftigt, Du hast zwar heute nichts getan, doch warst den ganzen Tag beschaeftigt. __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com
