Producers - Silicon Laboratories EFR32xG21 Wireless Gecko Reference Manual

FNSEL value
0xA
0xB
0xC
0xD
0xE
0xF
The default value of FNSEL is 0xC, meaning that the input from the selected producer goes through unchanged. This feature can be
used to combine multiple channels to get even more complex functions.

13.3.3 Producers

Through SOURCESEL in PRS_SYNCHx_CTRL or PRS_ASYNCHx_CTRL, each PRS channel (synchronous and asynchronous re-
spectively) selects its signal producers. Each producer outputs one or more signals which can be selected by setting the SIGSEL field.
Setting the SOURCESEL bits to 0 (Off) leads to a constant 0 output from the input mux regardless of SIGSEL.
The GPIO producer signals depend on settings in the GPIO module. They are selected using the edge interrupt configuration settings
described in 24.3.10.1 Edge Interrupt
For example, to route PB00 as a producer for PRS channel 2, EXTI0, EXTI1, EXTI2, or EXTI3 should be configured to connect to
PB00, and the corresponding GPIO PINx should be selected as the PRS channel 2 producer. If we choose EXTI1 via PRS producer
"GPIO PIN1":
1. GPIO_EXTIPSELL_EXTIPSEL1 = PORTB, and GPIO_EXTIPINSELL_EXTIPINSEL1 = PIN0 connect PB00 through the EXTI1 sig-
nal.
2. PRS_ASYNC_CH2_CTRL_SOURCESEL = GPIO, and PRS_ASYNC_CH2_CTRL_SIGSEL = PIN1 connects the PIN1 (EXTI1)
signal to asynchornous PRS channel 2 as a producer.
silabs.com | Building a more connected world.
Generation. PIN0 uses settings for the EXTI0 interrupt, PIN1 uses settings for EXTI1, and so on.
Implemented Function
B
A OR (NOT B)
A
(NOT A) OR B
A OR B
1
Reference Manual
PRS - Peripheral Reflex System
Rev. 0.4 | 285