54L15 PTA coex with external wifi

RE: 54L15 PTA coex with external wifi

Asbjørn — Mon, 08 Dec 2025 14:42:06 GMT

Hello William

Q1:

General description:

https://docs.nordicsemi.com/bundle/ncs-3.1.0/page/nrfxlib/nrf_802154/doc/wifi_coex_module.html

https://docs.nordicsemi.com/bundle/ncs-latest/page/nrf/samples/wifi/ble_coex/README.html

The timing isn't standard as it will depend on the product and traffic. So the request lead time will depend on the WiFi chip they are using. Are they sure it's a good idea to switch the roles around and deviate from having the WiFi control the antenna? How have they tried to debug the grant pin not asserted on the WiFi chip? It's a standard interface and should respond to the request. The wifi chip is the one that grants antenna access, so it should control the grant pin as needed and respond to the BLE requests. It sounds like the WiFI TX is working, but the WiFi RX isn't working as the BLE is granted access to the antenna when the WiFI is supposed to do RX? Does the BLE functionality work as expected?

Q2:

All GPIOs starting with P2. is on port 2.

Best regards

Asbjørn

RE: 54L15 PTA coex with external wifi

William.wei — Fri, 05 Dec 2025 14:28:12 GMT

i mean
1. is the timing sequence correct in this figure？

requst pin will be held for such a long time?

if there is a docs about the details of our PTA?

2. all these three pins should not use P2? which pin is gpio not gpiote?

[quote userid="2729" url="~/f/nordic-q-a/125963/54l15-pta-coex-with-external-wifi/556347"]You can't use P2 for the pins. P0 or P1 have to be used for the gpio based coex interface[/quote]

Regards,

William,.

RE: 54L15 PTA coex with external wifi

Asbjørn — Fri, 05 Dec 2025 14:12:42 GMT

Hello William,

You can't use P2 for the pins. P0 or P1 have to be used for the gpio based coex interface.

[quote user="William.wei"]the key point is if time costs for request will cover the time of grant, i am not sure of this.[/quote]I don't understand what you mean here? Can you ellaborate a bit what your concern is?

Best regards

Asbjørn

RE: 54L15 PTA coex with external wifi

William.wei — Thu, 04 Dec 2025 03:18:34 GMT

thanks Asbjorn,

the key point is if time costs for request will cover the time of grant, i am not sure of this.

another question is coex pins must using P0 and P1,right, P2 doesn't have GPIOTE in 54L15. or for 3 wires coex, which pin can use P2 port, whch pin can't use P2 port?

Regards,

William.

RE: 54L15 PTA coex with external wifi

Asbjørn — Wed, 03 Dec 2025 16:32:02 GMT

Hello William,

in theory the approach you suggest would work, but I don't know which signals they have available and are using with the external WiFI module now? If they can block WiFi foe the duration of the BLE events and let the BLE be in charge, then it will work as you suggest.

It might be useful to explore and understand why the grant for RX functionality isn't working if they expect that to be better way to use the setup. Are the signals they have looking and behaving as expected if they look at them with a signal analyser?

Best regards

Asbjørn