As defined in the LTPI Specification, the SMBus/I2C bus requires a more complex, event based, transfer than GPIO and UART. SMBus/I2C has a controller device on one LTPI side (SCM or HPM) and the target device on the other (HPM or SCM). LTPI provides a transfer of commands and data for SMBus/I2C between SCM and HPM according to the LTPI specification r 1.2, v 1.0RC3 .
There are two possible SMBus/I2C rates:
- 100 kb/s
- 400 kb/s