14.6.5.1 Overview

To determine the exact timing of an incoming frame, for example for beaconing networks, the reception of this frame can be signaled to the microcontroller via AT86RF212B pin 10 (DIG2). The pin turns from L to H after detection of a valid PHR. When enabled, DIG2 is set to DIG2 = H at the same time as IRQ_2 (RX_START) occurs, even if IRQ_2 (RX_START) is disabled. The pin remains high for the length of the frame receive procedure.

This function is enabled with the IRQ_2_EXT_EN bit in the TRX_CTRL_1 register (TRX_CTRL_1.IRQ_2_EXT_EN). Pin 10 (DIG2) can be connected to a timer capture unit of the microcontroller.

If this pin is not used for RX Frame Time Stamping, it can be configured for Antenna Diversity. Otherwise, this pin is internally connected to ground.

Figure 14-64. Timing of RX_START and DIG2 for RX Frame Time Stamping within 250kb/s O-QPSK mode
  1. Timing figures tIRQ refer to the Digital Interface Timing Characteristics.