i2c read word for double byte not working as expected

[sonelu]

If the device has 8 bit defined registers and you have a 'low' and a 'high' value for a measure (ex. for accelerometer or gyro) using i2c read_word_data will not work as it will not return the two successive registers, but the first register twice.

Need to define a 'byte', 'word' property of the register to deal with 'word' type of registers and be able to read them correctly in i2c.

[sonelu]

read_word is not supposed to be used to read two successive byte registers. SMBus will simply return the first byte register twice.

We implemented a few changes in BaseRegister by introducing an attribute word that is default False and can be switched to True for real word based registers.

We also allow size > 1 for I2C devices, in which case the read and write will make successive calls to read_byte and write_byte and compose the value of the register. We also introduced an order attribute in BaseRegister that allows handling of low-high register sequence or high-low.

Might be worth checking if other read or write functions can be used to speed up the reading of several registers in one go.