ANT_SEL selects the antenna interface used during RX or TX. Antenna interface control is specified in the following table.

Table 1. Antenna switch control with ANT_SEL in different states
State ANT_SEL Description
Power-down X Antenna switches disabled (isolating)
Program X Antenna switches disabled (isolating)
UICR program X Antenna switches disabled (isolating)
Receive 0 ANT1 enabled, ANT2 disabled
1 ANT1 disabled, ANT2 enabled
Transmit 0 ANT1 enabled, ANT2 disabled
1 ANT1 disabled, ANT2 enabled