I3C Characteristics Registers

The I3C Target module contains two registers that describe and define the module’s capabilities and functions on the I3C bus – the I3CxBCR Bus Characteristics Register and the I3CxDCR Device Characteristics Register. The I3C Controller can read the value of these registers by passing GETBCR and GETDCR Common Command Codes (CCCs) respectively.

The I3CxBCR Bus Characteristics Register (BCR) describes the role and capabilities of the I3C Target module. Some BCR bits are hard-coded read-only bits, whereas some are user-selectable. Refer to the description of the I3CxBCR register for bit details.

The I3CxDCR Device Characteristics Register (DCR) value is user-selectable and describes the compliant device type for the I3C Target module. The default DCR value stored in the I3CxDCR register is 0xC6, which is defined by the MIPI specification to represent a ‘Microcontroller’ device.

Tip: A list of all DCR values specified by MIPI is available on their website at www.mipi.org/MIPI_I3C_device_characteristics_register.