Target_Time_Nanoseconds

The MAC sets this bit when the PPSCMD field (Bits[3:0]) in Register 459 (PPS Control Register) is programmed to 010 or 011. Programming the PPSCMD field to 010 or 011, instructs the MAC to synchronize the Target Time Registers to the PTP clock domain. The MAC clears this bit after synchronizing the Target Time Registers to the PTP clock domain The application must not update the Target Time Registers when this bit is read as 1. Otherwise, the synchronization of the previous programmed time gets corrupted. This bit is reserved when the Enable Flexible Pulse-Per-Second Output feature is not selected.

This register stores the time in (signed) nanoseconds. When the value of the timestamp matches the both Target Timestamp registers, then based on the TRGTMODSEL0 field (Bits [6:5]) in Register 459 (PPS Control Register), the MAC starts or stops the PPS signal output and generates an interrupt (if enabled). This value should not exceed 0x3B9A_C9FF when TSCTRLSSR is set in the Timestamp control register. The actual start or stop time of the PPS signal output may have an error margin up to one unit of sub-second increment value.