 configuration/data. The L2/L3 layer should use a guard timer when waiting on responses for error conditions. The L1 can be in IDLE, CONFIGURED, or RUNNING state. Initialization procedure moves the L1 from IDLE to RUNNING state via the CONFIGURED state. The initialization is complete when the L1 sends a SLOT.indication message to L2/L3. PHY API configuration messages include: PARAM to allow the L2/L3 layer to collect information about the PHY configuration and current state. It is an optional exchange. CONFIG to allow the L2/L3 layer to configure the PHY. START to instruct the configured L1 to start transmitting as a gNB. STOP to move the L1 from running. Restart of the L1 can be accomplished by a STOP procedure followed by a START procedure using the same configuration. Slot procedures are used to control the DL and UL frame structures and to transfer data between the L2/L3 and Ll. Procedures supported by the PHY API include: Transmission of 125us, 250us, 500us, or 1Ms SLOT message. The periodicity of the SLOT. indication message is dependent on the numerology where the number of messages per subframe is highlighted, such as 500 us for FR1/ < GHz operation with 30 KHz Subcarrier Spacing or 125 us for FR2/mmWave operation with 120 Khz subcarrier spacing. Synchronization of Single Frequency Network (SFN)/Slot between the L2/L3 and PHY. Used to maintain a consistent SFN/SL value between L2/L3 and Ll. Configuration can be set to have the L2/L3 be the master or the L1 be the master. Per-Channel Transmit APIs Transmission of the Broadcast Channel (BCH) transport channel used to transmit the Master Information Block on the Physical Broadcast Channel (PBCH). Transmission of the PCH transport channel. PCH transport channel is used to transmit paging messages to the User Equipment (UE). The UE has specific paging occasions where it listens for paging information. The L2/L3 is responsible for calculating the correct paging occasion for a UE while the L1 is only responsible for transmitting PCH PDUs when instructed by the D