Serial Port 2

RE: Serial Port 2

Sigurd Hellesvik — Mon, 06 Sep 2021 11:57:25 GMT

You are right of course, the pins are in hex. Good find!

For an example of an overlay file, see the lpuart sample and the file [YOUR_PATH_TO]/ncs/nrf/peripheral/lpuart/boards/nrf5340dk_nrf5340_cpuapp.overlay

I can also recommend the nRF Connect SDK Tutorial - Part 2, as it describes how to change the device tree.

Regards,
Sigurd Hellesvik

RE: Serial Port 2

saeed mahvis — Mon, 06 Sep 2021 05:05:24 GMT

Hi again

Actually the pin numbers you mentioned for Tx nd Rx of Uart0 are in HEX format .It means that we should

use P0.20 and P0.22 at gpio. I used P0.20 as Tx and it worked properly.

Now I want to changed these pins by using the .overlay file .For example I want to use P0.10 and P0.9

as Tx and Rx of Urat0.

How can I do this?

Thank you in advance for paying attention.

RE: Serial Port 2

Sigurd Hellesvik — Mon, 16 Aug 2021 06:21:55 GMT

Yes, you can use nRF Connect app for mobile.

Regards,
Sigurd Hellesvik

RE: Serial Port 2

saeed mahvis — Sun, 15 Aug 2021 03:48:49 GMT

Hi again

I am just trying to use P0.16 and P0.14.

Still I have another question. With which mobile app I can receive data?

Can I use nRF Connect app or I shall use another app?

RE: Serial Port 2

Sigurd Hellesvik — Tue, 10 Aug 2021 13:40:48 GMT

Can you try use P0.16 as RX and P0.14 as TX?

Regards,
Sigurd Hellesvik

RE: Serial Port 2

saeed mahvis — Tue, 10 Aug 2021 12:22:39 GMT

/*
* Copyright (c) 2020 Nordic Semiconductor ASA
*
* SPDX-License-Identifier: Apache-2.0
*/

/dts-v1/;
#include <nordic/nrf5340_cpuapp_qkaa.dtsi>
#include "nrf5340_cpuapp_common.dts"

/ {
model = "Nordic NRF5340 DK NRF5340 Application";
compatible = "nordic,nrf5340-dk-nrf5340-cpuapp";

chosen {
zephyr,sram = &sram0_image;
zephyr,flash = &flash0;
zephyr,code-partition = &slot0_partition;
zephyr,sram-secure-partition = &sram0_s;
zephyr,sram-non-secure-partition = &sram0_ns;
};
};

&spi2 {
compatible = "nordic,nrf-spim";
status = "okay";
sck-pin = <47>;
miso-pin = <46>;
mosi-pin = <45>;
};

&usbd {
compatible = "nordic,nrf-usbd";
status = "okay";
};

The above code is the nrf5340dk_nrf5340_cpuapp.dts file in NSC.As you can see there is no

Uart configuration code in this file.

RE: Serial Port 2

Sigurd Hellesvik — Tue, 10 Aug 2021 11:48:35 GMT

It was not wrong, the zephyr.dts file contains the compiled device tree, meaning that RX should be P0.16 and TX should be P0.14.
See the Zephyr link overview on more information on the Zephyr build process.

I am sorry, I was mistaken on the 0x16 and 0x14.

In the "nrf52840dk_nrf52840.dts" file, the correct pins are listed

Here pins are P0.06, P0.08, P0.05 and P0.09.

In the nRF5340, the peripherals can be configured to use different pins. This is set from registers in the nRF5340. However, in NCS, you do not need to write to these registers manually. Instead, you configure the pins using ".dts" or ".overlay" files, and NCS automatically configures the nRF5340.

This means you can change what pins you want to use for TX and RX if needed.

Regards,
Sigurd Hellesvik

RE: Serial Port 2

saeed mahvis — Tue, 10 Aug 2021 11:26:02 GMT

Hi again

Actually I don't understand the meaning of <0x16> and <0x14>.What is its equivalent GPIO pin number

in NRF5340-DK development board. As far as I searched the schematic of this board I couldn't find RX

and TX pins of Uart_0 to which you can connect your serial device.

RE: Serial Port 2

saeed mahvis — Tue, 10 Aug 2021 11:13:22 GMT

Hi again

Actually I don't understand the meaning of <0x16> and <0x14>.What is its equivalent GPIO pin number

in NRF5340-DK development board. As far as I searched the schematic of this board I couldn't find RX

and TX pins of Uart_0 to which you can connect your serial device.

RE: Serial Port 2

saeed mahvis — Tue, 10 Aug 2021 11:12:35 GMT

Hi again

Actually I don't understand the meaning of <0x16> and <0x14>.What is its equivalent GPIO pin number

in NRF5340-DK development board. As far as I searched the schematic of this board I couldn't find RX

and TX pins of Uart_0 to which you can connect your serial device.

RE: Serial Port 2

Sigurd Hellesvik — Tue, 10 Aug 2021 06:51:26 GMT

Uart 0 use pins 0x13, 0x14, 0x15 and 0x16. I found this in the zephyr.dst file:

You can use other pins than these.
In that case you need to change the pin configurations, you need to change the device tree. The nRF Connect SDK Tutorial - Part 2 describes how to change the device tree. I recommend the whole three part tutorial for learning how to work with NCS, it explained the concepts very well.

You should use 3.3v:
Look at the GPIO levels in the Regulators documentation of the nRF5340.

Regards,
Hellesvik

RE: Serial Port 2

saeed mahvis — Tue, 10 Aug 2021 03:34:55 GMT

Thank you very much for your paying attention.

Yes the peripherial_uart sample seems to be a good choice for my project. But Uart 0 pins didn't come out on GPIO connector

pins in NRF5340-DK development board. Can I use Uart 1 instead of Uart 0 in the peripherial_uart sample and if it is possible what is

the logic level I should use 5v or 3.3v?

RE: Serial Port 2

Sigurd Hellesvik — Fri, 06 Aug 2021 06:50:16 GMT

Hi Saeed

From the luetooth: Peripheral UART documentation:
"When connected, the sample forwards any data received on the RX pin of the UART 0 peripheral to the Bluetooth LE unit."

This sample will send data from RX pin of UART via Bluetooth.
Does this answer your question?

Regards,
Sigurd