37.2.6.2 Dynamic Address Assignment Procedure
0). If the Target already has a Dynamic Address
assigned or is a Hot-Joining device (HJCAP = 1), it passively NACKs the Active Controller and
waits for the Stop condition (Hot-Joining devices are assigned a Dynamic Address through
a separate Hot-Join
Mechanism).1) and choose not to request a Hot-Join to always NACK
an ENTDAA CCC and not participate in the Dynamic Address Assignment procedure.During the Dynamic Address Assignment procedure, the Target (alongside all the other devices on the bus) sends its own 48-bit Provisional ID (I3CxPID5 through I3CxPID0), Bus Characteristics Register (I3CxBCR), and Device Characteristics Register (I3CxDCR) in Open-Drain mode to participate in arbitration. Due to the nature of the I3C bus, the Target wins the arbitration if it has the lowest concatenated value of the Provisional ID, BCR, and DCR.(1)
0b01), and sets the Dynamic Address Changed DACHIF interrupt flag. If the parity is invalid, the Target passively NACKs
the Active Controller and waits for the next arbitration round.The Dynamic Address Assignment procedure is outlined in Figure 37-18 below. Figure 37-19
shows the frame format for a typical Dynamic Address Assignment procedure. The Dynamic
Address Assignment uses Open-Drain signaling, except when the Controller is transmitting
a Restart followed by the Broadcast Address 7'h7E/R, in which case
Push-Pull signaling is used.
- The Target loses Dynamic Address
Arbitration when it releases the SDA line to transmit a ‘
1’, but another device on the bus drives it low to transmit a ‘0’. - The Dynamic Address assigned by the Active Controller incorporates the priority level assigned to the Target for servicing In-Band Interrupt (IBI) requests. Refer to In-Band Interrupt (IBI) for details.
- The Active Controller can abort the Dynamic Address Assignment procedure anytime by sending the Stop condition. The Active Controller can also restart the procedure anytime by sending the ENTDAA CCC.