# 171 questions

Tagged
• x
30
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## nrf52 GPIO sink & source current

Hi, I'm contemplating ways to drive a small RGB LED matrix with the nrf52832 in a really space-tight project. Ideally without any external components. I'ts maybe around 40 RGBs (5x8 grid, 120 individual LEDs to drive).

Charlieplexing would ... (more)

50
views
1
vote
2

## Setting GPIO pin as output pin

I am using nrf51822 DK. How to set GPIO pins as output pins and access the pins to set or reset the output.For example if I want to use pin 20 as output, how to configure that.I need ... (more)

82
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3
1

## Change Pin from Input to Output in runtime?

Hi, i have nrf52 and sdk13.1. Is this possible. I get NRF_ERROR_INVALID_STATE.

44
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1
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1

## Will GPIOTE Interrupt be generated when CPU is halted?

When performing flash operations, i.e. via FDS or FSTORAGE, etc. - will GPIOTE events be captured and 'queued' until the CPU is no longer halted?

Said another way:

Can I assume that a GPIO transition that occurs while CPU is ... (more)

46
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1
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1

## Enable pins 9 and 10 as GPIO on NRF52

Hi All,

I am developing a ble applications and am unable to get pins 9 or 10 to work as gpio. I understand that this is because, by default they are used by the NFC.

I have tried the following ... (more)

52
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## NFC Usage as GPIO Pins

Hi all,

I am trying to configure the NFC Pins for usage in an SPI application. However they do not even work for a simple nrf_gpio_pin_set after configuring them with nrf_gpio_cfg_output . Every other Pin seems to work, though.

After some ... (more)

53
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3
1

## gpio pin as power source for other

Hello! Can I use one of the gpio pin as power source directly for other MC on my board (hx711 - ADC with current consumption in normal mode 1.5ma (from datasheet)). I understand I have to do it via transistor ... (more)

54
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1

## NRF51822 generate pulse with GPIO

I am trying to use NRF51822 GPIO to generate a pulse with max width of 0.3us. According to other tickets in the forum and the product spec, NRF51822 should be able to generate a 50% duty PWM with 8MHz ... (more)

54
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2

## ADC with internal pull up

This is for the nRF51822.

I have done some tests where I configure a pin as input with pull up enabled and then reconfigure the pin for an adc measurement with 1/3 prescaler with band gap reference.

It looks ... (more)

1k
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5
2

## max gpio current for nRF52

Hello, I just wanted to update previous similar questions for the nRF52 series, old one for nRF51 is here: https://devzone.nordicsemi.com/questi...

At page 151, section 20.4, of the nRF52832 Product Specification v1.0 I find that ... (more)

168
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## nRF52 reset behaviour on GPIO output pins

Hi. I have a board here based on the nRF52832, using SD 132 and SDK 13.0.0, with a modem on it that I'd like to keep powered on even when the Nordic is in system off mode ... (more)

77
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1
vote
1

## Minimum pulse length to detect low level with GPIO SENSE for nRF52

Hi all

What is the minimum required length of a LOW pulse to be detected by the nRF52832 via GPIO SENSE mechanism? I couldn't find it in the product specification.

I want to wakeup the nRF with a LOW ... (more)

63
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1

## Small problem with using the GPIO to power system ON/OFF

Hi, I am really new to the Nordic products and programming for that matters. But, the thing is that I am in somewhat of a hurry. I would like to use a similar code to below to the one below ... (more)

64
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## What happens to nRF51822 if GPIO is set to source less current than required?

I have a board with some LEDs that are driven in the same way as with the nRF51 DK board (i.e. there is a resistor in series with the LED and you drive the pin low to turn the ... (more)

131
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## nRF52832 one of output (p0.15) lost its power

Hi!

I have noticed strange problem with one of GPIOs - P0.15. We have tested 50 devices based on nRF52832 and 3 of them have problem with P0.15 after few days.

P0.15 pin we have connected with two ... (more)

147
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## How to send 1 byte via SPI from master to slave

Hello everyone, I'm trying to run my nrf51 with ADS1298 using SPI. nrf51 is master and ADS1298 is slave.

I configured SPI as

const nrf_drv_spi_config_t spi_config =
{
.sck_pin = 25,
.mosi_pin = 24,
.miso_pin = 23,
.ss_pin = 30,
//.irq_pin = 22,
.irq_priority = APP_IRQ_PRIORITY_HIGH,
.orc ...
(more)

84
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3
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## I want to digital high a gpio pin on nrf51dk, when I receive the text say "ON" from my android smartphone.How can I accomplish that using the nrf ble app uart example.I am not sure where I can compare the incoming ble data [closed]

Toggling a gpio pin upon receiving a particular string from ble uart app

89
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1
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1

## Interference of bsp-module while re-configuring NFC-pins as GPIOs

Hello,

on my custom board I am trying to use pin P0.09 and P0.010 for interrupt-purposes. So I integrated the necessary adjustments as mentioned in this topic here, which resulted in an immediate 'halt' of my board, upon ... (more)

170
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1
vote
3

## Problem using GPIO- and BSP-module simultaneously

Hello,

last week I was trying to integrate a wake-on-motion-functionality for my hardware using some interrupt-handling. While that problem is solved, I came across some kind of interdependency between initializing the GPIO- and the BSP-module simultaneaously.

Here is the code ... (more)

100
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1

## Hardfault when using both UART and GPIOTE, how can I solve this problem?

Hello,

I feel like this question has an answer similar to this question, but I can't seem to get it working https://devzone.nordicsemi.com/questi...

I am using the nrf51422 chip on a board I designed myself and ... (more)

66
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1

## nRF5 with input-multiplexer on ADC pin, optimization required

Hey, I am trying to sample from 10 analog sensors and stream the results via bluetooth. Since the nRF5 is on a board that only lets me access 5 Pins, I am using a 16:1 multiplexer connected to a ... (more)

222
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1
vote
2

## Is it physically possible to set UART RX and TX to same GPIO pin?

I'm trying to implement send && recieve through one wire. Handling of pin state, if it is input or output is done via SW. Also it is going to be half-duplex only.

Is it possible to do something like this ... (more)

51
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3
1

## GPIO act incorrectly when building with GCC

Hi,

I connected 74CH595 shift registers to nRF52DK board. When I built and upload my code with Keil everything works just fine, but if I compliled it with GCC and upload with nrfjprog, the 74CH595 cannot act properly. I need ... (more)

226
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1

## Taiyo Yuden EYSHJNZXZ (nRF52832) cannot use NFC pins as GPIO

I am having trouble using GPIO P0_9 and P0_10 as GPIO pins. These are the pins designated as NFC1 and NFC2.

I am using the following sample code:

#include <stdbool.h>
#include <stdint.h>
#include "nrf_delay.h"
#include "boards.h ...
(more)

137
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1
vote
1

## High Drive mode downsides (nRF52)

Hi,

I just had a quick question - currently I'm using standard drive mode for everything, however in one case I'm driving an IR transmitter that could really do with a little more current.

What are the downsides of ... (more)

84
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1

## What are the characteristics of the nRF52832 GPIO internal 'ESD structures'?

What are the following characteristics for the 'ESD structures'/diodes pictured?

Reverse breakdown voltage, rated forward current, forward voltage

73
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## Cannot pull down a GPIO pin which is shared with LED

Hi,

I added following code in saadc example code to set GPIO pin high/low and monitor it in the terminal. The pull up looks ok, but when I set it to low, the reading never goes down to 0 ... (more)

89
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## Turn PWM off and back on

I am using Nordic SDK to develop an application. I need to turn PWM off and turn it back on (to produce a beeping sound from a buzzer). To do this I went into the bsp.c file and added ... (more)

477
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3
3

## Configuring MISO pin for SPIM nrf52

Greetings I am working on an application that logs data to SPI flash device. I am having an issue where it appears that the pin configured as a MISO for SPIM is garbling up the flash device's responses. I ... (more)

84
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no

## Turn off PWM LED [closed]

I have a BLE device that is using Nordic SDK 8.1 and uses PWM to control an LED. Now I want to turn the led off with PWM. To do this I set the duty cycle to 0 and ... (more)

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