14.2.1.4.4 BUSY_TX to RX_ON States

The transition from PLL_ON to BUSY_TX state and subsequently to RX_ON state is shown in the figure below.

Figure 14-24. PLL_ON to BUSY_TX to RX_ON Timing for O-QPSK 250kb/s Mode

Starting from PLL_ON state, it is further assumed that the PLL has already been locked. A transmission is initiated either by a rising edge of pin 11 (SLP_TR) or by command TX_START. The PLL settles to the transmit frequency and the PA is enabled. After the duration of t_TR10 (one symbol period), the AT86RF212B changes into BUSY_TX state, transmitting the internally generated SHR and the PSDU data of the Frame Buffer. After completing the frame transmission, indicated by IRQ_3 (TRX_END), the PLL settles back to the receive frequency within t_TR11 = 32µs and returns to state PLL_ON.

If during BUSY_TX the radio transmitter is requested to change to a receive state, it automatically proceeds to state RX_ON upon completion of the transmission.