Regarding the signal logic/level behavior of the generic three-wire coexistence

One of my customers currently has a requirement similar to the one discussed in this ticket:  54L15 PTA coex with external wifi 


In their product, the main controller is a BES2610, and the Bluetooth functionality is handled by our nRF54L15. They are using the generic three-wire coexistence configuration to arbitrate RF antenna access between the BES2610 and the nRF54L15.

/ {
      nrf_radio_coex: radio_coex_three_wire {
         status = "okay";
         compatible = "generic-radio-coex-three-wire";
         req-gpios =     <&gpio0 24 (GPIO_ACTIVE_HIGH)>;
         pri-dir-gpios = <&gpio0 14 (GPIO_ACTIVE_HIGH)>;
         grant-gpios =   <&gpio0 25 (GPIO_ACTIVE_HIGH | GPIO_PULL_UP)>;
   };
}

https://docs.nordicsemi.com/bundle/ncs-2.9.1/page/nrf/app_dev/device_guides/wifi_coex.html#enabling_generic_three-wire_coexistence

They have a specific question regarding the three-wire setup:

req-gpios: This is the request signal sent by the nRF54L15 when it requires the RF antenna.
grant-gpios: This is set high by the BES2610 to grant antenna access to the nRF54L15.
What is the exact logic for pri-dir-gpios? I have reviewed the nRF7001 SR Timing Documentation, but it does not clearly define how the nRF54L15 Bluetooth stack controls this GPIO. Specifically, what is the logical behavior of pri-dir-gpios during various Bluetooth events, such as scanning, advertising, and active connections?

BR

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