SPRUJ28E November 2021 – September 2024 AM68 , AM68A , TDA4AL-Q1 , TDA4VE-Q1 , TDA4VL-Q1
In case of I3C messaging, asymmetric generation pattern for driving SCL can be enabled. The main purpose for this feature is supporting I3C slaves that are not capable to use maximal SCL frequency during private read/write data transfers. Host can recognize limited speed device by examining value of I3C_DEV_IDn_RR2[15-8] bit-field for n = 0 to 11. Maximum frequency supported by slave can be retrieved by GETMSCL command. The low period of SCL is extended by the value programmed in I3C_PRESCL_CTRL1[15-8] PP_LOW bit-field, which can be calculated using the following equation:
The I3C_PRESCL_CTRL1[15-8] PP_LOW resolution is set to ¼ of SCL period. The high period of the SCL remains unchanged and is equal to half period of I3C frequency.
The low period used in push-pull mode for slaves with limited SCL capability results from following equation: