P4 main processor + C6 Wi-Fi co-processor + External H2 Thread radio co-processor: How coexistence/PTA is handled? (TZ-1918)

[dmartauz]

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Issue or Suggestion Description

OTBR example for P4 with WiFi is described here:
https://github.com/espressif/esp-thread-br/blob/main/examples/basic_thread_border_router/README_esp32p4.md

However, there are no PTA pins for RF coexistence connected:

How coexistence/PTA is handled in this example?

[zwx1995esp]

Hi, the PTA feature is a feature that enhances the transmission performance when there are channel conflicts between the Wi-Fi and Thread networks. In the solution based on the P4 + H2 + C6 development board, the C6 is used to send and receive Wi-Fi packets, while the H2 handles Thread packet transmission and reception. Therefore, it is only necessary to connect the PTA lines between the C6 and H2.

[dmartauz]

@zwx1995esp thank you for your answer. Are PTA pins of C6 (running esp_hosted) configurable?

[zwx1995esp]

Yup. But we did not support the configurations in the Kconfig, you can refer to this API: ot_br_external_coexist_init to configure the PTA pins on C6.