Unable to establish communication between a nRF52840-Dongle, programmed with the HCI_uart example, and a Raspberry Pi 3 B+

RE: Unable to establish communication between a nRF52840-Dongle, programmed with the HCI_uart example, and a Raspberry Pi 3 B+

JONATHAN LL — Mon, 12 Oct 2020 07:39:00 GMT

I was thinking that you could use the nrf52-dk instead of the dongle. try to use the I/O pins on the dk and connect it to the RPi's GPIO in the same way you tired the dongle. Then you could see if the same behaviour happens with the 52-dk. if so then i think we can assume its on the RPi side and try something else

Here are some hopefully helpful links:
https://devzone.nordicsemi.com/f/nordic-q-a/39998/maximum-number-of-ble-slaves-with-rpi-master
https://github.com/NordicSemiconductor/pc-ble-driver
https://devzone.nordicsemi.com/f/nordic-q-a/17783/nrf52832-hci-firmware
https://devzone.nordicsemi.com/f/nordic-q-a/39106/nrf52840-dongle-to-raspberry-pi-b
https://github.com/nicslabdev/NRF52840-Beacon_Scanner

We do not have a sample project other than HCI_UART in the nrf-connect-sdk.
Regards,
Jonathan

RE: Unable to establish communication between a nRF52840-Dongle, programmed with the HCI_uart example, and a Raspberry Pi 3 B+

matt_C — Wed, 07 Oct 2020 17:17:00 GMT

I have an nRF52840-DK I could test with. Do you have a sample project that would use the nRF52840-Dongle HCI_UART as a peripheral?

Thanks,

Matt

RE: Unable to establish communication between a nRF52840-Dongle, programmed with the HCI_uart example, and a Raspberry Pi 3 B+

JONATHAN LL — Wed, 07 Oct 2020 09:12:14 GMT

Hi,

To change the baud rate edit this; current-speed = <Baud Rate>; in the overlay file.

I will test it out and se if i am able to find a solution, it might take some time as i don't have a RPi atm.
I will update you on any progress.

Do you have any other 52 devices? a 52DK or something that you could test with maybe ?

Regards,
Jonathan

RE: Unable to establish communication between a nRF52840-Dongle, programmed with the HCI_uart example, and a Raspberry Pi 3 B+

matt_C — Tue, 06 Oct 2020 19:40:46 GMT

I agree that the problem is most likely on the RPi side of things, I am hoping that the testing that was done by Nordic to validate the HCI_UART can help illuminate how I can make It work with the RPi.

Following is my post to the RPi forum, https://www.raspberrypi.org/forums/viewtopic.php?f=28&t=287232

RE: Unable to establish communication between a nRF52840-Dongle, programmed with the HCI_uart example, and a Raspberry Pi 3 B+

matt_C — Tue, 29 Sep 2020 12:58:52 GMT

I will look over the links you sent.

Where do I need to modify the HCI UART example to set the lower baud rate, since 1Mbit/s is the default uart setting?

I haven't tried the RPi forum, but I have made the following post on the Balena forums. forums.balena.io/.../193535

RE: Unable to establish communication between a nRF52840-Dongle, programmed with the HCI_uart example, and a Raspberry Pi 3 B+

JONATHAN LL — Tue, 29 Sep 2020 07:15:37 GMT

Hi Matthew sorry for the late reply,
What you have done seems to be correct for the dongle, but I would recommend testing whit a lower baud rate.
Alternatively here is a link to a blog post for Linux use. I think maybe the problem is on the RPi side of things, I don't ha a RPi to test right now but can try to get a old of one an se if i can reproduce the error.
Have you checked out the RPi forum to see if there are some similar cases? I vas able to find this one, maybe it helps?
Regards,
Jonathan

RE: Unable to establish communication between a nRF52840-Dongle, programmed with the HCI_uart example, and a Raspberry Pi 3 B+

matt_C — Thu, 24 Sep 2020 15:43:29 GMT

Sorry for the confusion. I am not connecting to P0.16 on the dongle. Following are my connections.

nRF52840-Dongle			Raspberry Pi 3 B+
Signal	Pin		Signal	BCM Pin	40-pin header pin
RX	P1.10	<—->	TXD0	GPIO14	8
TX	P1.13	<—->	RXD0	GPIO15	10
CTS	P0.29	<—->	CTS0	GPIO16	36
RTS	P1.15	<—->	RTS0	GPIO17	11

Following is my Zephyr device tree overlay for the nRF52840-Dongle.

/* SPDX-License-Identifier: Apache-2.0 */

&uart0 {

compatible = "nordic,nrf-uart";

current-speed = <1000000>;

status = "okay";

tx-pin = <45>;

rx-pin = <42>;

rts-pin = <47>;

cts-pin = <29>;

hw-flow-control;

};

RE: Unable to establish communication between a nRF52840-Dongle, programmed with the HCI_uart example, and a Raspberry Pi 3 B+

JONATHAN LL — Thu, 24 Sep 2020 15:07:32 GMT

Hi Matthew,

[quote user=""]UART0_CTS (GPIO16)[/quote]

The P016 is not connected to anything on the nrf52dongle, ref

So try changing it to one of the I/O that are accessible.

Regards,
Jonathan