Receive data via uart with nrf5340

[brando14]

hello, I am currently working on a project that involves sending data via serial from a device to the nordic nr5340.

but I can't find an example that shows how it would be in this case, in the course it tells me to use the asynchronous api, but in this case it is to enter the parameters in the console, so I would like you to please tell me an example so that I can make the configuration.

Currently what I know is that a configuration must be made to specify the pins since by default the nrf5340 receives is through the gpios that are connected to the usb, however in the case of how the data is handled it is still confusing for me

So could you please tell me where to start.

[helsing]

Hello,

What will you be communicating with? What are the requirements for your application? If low power is important, then I suggest you have a look at the Low Power UART(lpuart) sample.

As you may know, if you click 'Browse' next to "Application template" in VS Code you can search for 'uart' to get a long list of relevant samples. However, we are happy to guide you further.

Currently what I know is that a configuration must be made to specify the pins since by default the nrf5340 receives is through the gpios that are connected to the usb, however in the case of how the data is handled it is still confusing for me

You may use an .overlay file to specify which pins to use for the UART on the nRF5340 DK. I could get back to you with an example.

[brando14]

hello, thanks for answering me, the connection will be with another board which transmits the information given by a sensor connected to it, through uart, at the moment they are a numerical data, my idea is that the nordic receives the information and prints it on the console at the moment.

[helsing]

It sounds like lpuart should be suitable for this application. Any questions so far?

[brando14]

hello, thanks for the reply and sorry for the delay in responding, well What I really want to do is the following:

1) I have a sensor that sends the following numerical data through uart:

2) What I want to do is use one of the sdk apis, preferably the asynchronous one that is the one I use in the course to be able to access that data using the nrf5340.

Currently I already managed to configure so that the rx and tx pins are in the gpio P1.14 and P1.15 respectively, and I have them connected, and I tried the connection and the interface indicates that it is online.

However, what is not clear to me is how to receive the data, so I would like to know if there is not a simple example with that api for this type of case.

I am new to using the device and any information you can provide me would be greatly appreciated.

[helsing]

Hi brando, I will get back to you after the weekend.

[brando14]

ok, thank you for the reply i will wait 

[helsing]

Have you tried running the example from Lesson 5 of the devacademy course? You could try to printing rx_buf.

There is also another sample demonstrating asynchronous UART. Please note that sample was tested using nRF Connect SDK v1.9.1. I suggest testing it using v1.9.1 before migrating it to v2.x.x.

[brando14]

hello greetings, I have been using that example as a base, but from what I understand is that this example is to be used with the console, and I do not fully understand how it would be for my case, since I currently have the following:

1) I have 1 pcb connected via serial to nordic via pins 14 and 15, using the following configuration in my overlay file.

&uart1 {
		compatible = "nordic,nrf-uarte";
		reg = <0x8000 0x1000>;
		interrupts = <8 NRF_DEFAULT_IRQ_PRIORITY>;
		status = "okay";
		current-speed = <115200>;
		pinctrl-0 = <&uart1_default>;
		pinctrl-1 = <&uart1_sleep>;
		pinctrl-names = "default", "sleep";
};

&uart1_default {
		group1 {
				psels = <NRF_PSEL(UART_TX, 1, 14)>;

		};
		group2 {
				psels = <NRF_PSEL(UART_RX, 1, 15)>;
			
		};
};
&uart1_sleep {
		group1 {
				psels = <NRF_PSEL(UART_TX, 1, 14)>,
				        <NRF_PSEL(UART_RX, 1, 15)>;					
		
		};
};

2) I am using the course example as a base, but I don't understand how to get the data, nor how to manipulate it. I know that in the callback function it tells me that I can access it but I don't understand how it does it and I would really like to have more clarity on that aspect.

[helsing]

Hi brando,

I will get back to you with more details.

[brando14]

hello thanks for answering this problem too i tried to run the uart example from dev academy course but every time i build it gives me the following error:

I tried to change the version, taking into account that in version 2.2.0 every time I build the application, some files are not generated in the zephir folder inside the build, but the error still persists, not only that but also when I try to pass it al nordic opens the folder where the segger part is, what do you suggest I do?

[helsing]

Hi brando,

Sorry for the delay.

brando14 said:

every time i build it gives me the following error:

Could you please check the build log from the 'terminal' tab in nRF Connect for VS Code?

Sorry, I am a little confused regarding what you are working on. Is nRF5340 connected to a sensor or to another MCU that has a sensor connected to it? What would you like to do with the data you receive over UART on nRF5340?

[brando14]

Hello I have the next scenario:

I work with two boards:

Texas PCB: EVM430-FR6047 MCU018 PCB Rev A

Nordic Semiconductor PCB: nRF5340 DK

The texas board is connected with a ultrasonic sensor and sends the flow volume data through uart protocol. So the idea if forwarding the data coming from the MSP430 (ultrasonic flow sensor) to the nRF5340 DK for further processing via uart.

So I am wiring both PCBs this way:

 J3: TXD (black cable) --> nRF5340 DK P1.15 

J3: RXD (purple cable) --> nRF5340 DK P1.14

I'm trying to use the dev academy example as a guide but it doesn't even work for me, it builds fine but every time I pass them to nordic it only opens the segger folder.

.