SPRUJB3 March 2024 AM67 , AM67A , TDA4AEN-Q1 , TDA4VEN-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 12-65 shows the SIP.