24.4.4.12 Group Address Support in Controller

The group address feature enables multiple I3C Target devices to share a single group address or multiple group addresses, allowing the Controller device to send a given I3C Message to all Target devices in the group at once rather than one at a time.

Controller supports group address related CCCs (SETGRPA CCC, RSTGRPA CCC, DEFGRPA CCC) as vendor-specific CCCs with the existing CCC transfer model.

Store the group addresses in the device address table as shown in Figure 24-33.

Figure 24-33. Data Bytes Format for GETCAPS CCC without Defining Byte
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The Controller can write to a group address just as it would to any I3C Dynamic Address. However, the Controller does not attempt to read data from I3C Devices using a group address. Both rules apply to private SDR and HDR Messages, and to Broadcast and Direct CCC commands.