Multi-transmit mode connection sequence

In Multi-transmit mode, the device re-transmits each packet MT times, for a total of (MT+1) transmissions. There is no delay between retransmissions, and the TX (transmitting) device never receives RF data between retransmissions. Each retransmission includes an RF initializer. A transmission event may include follow-on packets, each of which retransmit MT times. Devices ignore the Forced Sync (FS) parameter in Multi-Transmit Mode.

The firmware does not apply the RB and RO parameters to follow-on packets, meaning that once transmission has begun, it continues without interruption until the DIN buffer is empty or the device reaches the streaming limit (TT parameter). As with the first packet, the payload of each follow-on packet includes up to the maximum packet size (PK parameter) bytes, and the TX device checks for more pending data near the end of each packet. The device does not send follow-on packets until it finishes all retransmissions of the previous packet.

The TX device specifies the streaming limit (TT) as the maximum number of bytes that the TX device can send in one transmission event, which may consist of many packets. If the device reaches the TT parameter limit, the TX device forces a random delay of 1 to RN delay slots (exactly 1 delay slot if RN is zero). In Multi-transmit mode, the firmware counts each packet only once when tracking the streaming limit (TT), no matter how many times it is retransmitted.

When an RX (receiving) device receives a Multi-transmit packet, it calculates the amount of time remaining in the Multi-transmit event, and inhibits its own transmissions for the duration of the Multi-transmit event, plus a random number of delay slots between 0 and (RN-1). If the local RN parameter is zero, the delay is only for the calculated duration of the event. An RX device only needs to receive one of the transmissions, and it keeps the channel turned off until the TX device has completed transmission. If follow-on packets are received, the RX devices move to the new frequency and listen for the follow-on packet for a specific period of time.