SPRUJ17H March 2022 – October 2024 AM2631 , AM2631-Q1 , AM2632 , AM2632-Q1 , AM2634 , AM2634-Q1
In the MIR and FIR operation modes, the transmitter must send a serial infrared interaction pulse (SIP) at least once every 500 ms. The SIP informs slow devices (operating in SIR mode) that the medium is occupied.
Figure 13-57 shows the SIP.
When the SIP_MODE bit of the Mode Definition Register 1 is equal to 1 (MDR1[6]), the TX state machine will always send one SIP at the end of the transmission frame. When MDR1[6] is equal to 0, the transmission of the SIP depends on the SEND_SIP bit of the Auxiliary Control Register (ACREG[3]). The system (Host CPU) can set ACREG[3] at least once every 500ms. The advantage of this approach over the default approach is that the TX state machine does not need to send the SIP at the end of each frame, which may reduce the overhead required.