# 26,150 questions

60k
views
no
2

## pulse sensor amped with RFduino doesn't work

hello, my name is alessio and i'm italian. I have got a problem with "RFduino" and the "pulse sensor amped" ( heart rate) . I downloaded the library of the sensor in the official site but when I compile the code ... (more)

50k
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306
3

## How to minimize current consumption for BLE application on nRF51822 [closed]

How to minimize current consumption for BLE application on nRF51822

49k
views
27
1

What can I do about it?

46k
views
49
2

## What is connection parameters?

What are the connection parameters for a Bluetooth low energy link, and how do they affect performance?

41k
views
9
5

## Is there a serial port profile for BLE?

Is there any equivalent to the SPP profile from Bluetooth Classic? I've always used this as a way to transmit custom data using Bluetooth, but I can't seem to find anything equivalent for BLE.

39k
views
51
7

## How do I calculate throughput for a BLE link?

How can I calculate the maximum throughput for an application running on the nRF51822 and the S110, when connecting to different kind of Central devices?

37k
views
4
4

## nRF52 SDK Installation

I want to evaluate the nRF52 SDK, but don't get how to install it.

The Getting Started section mentions an MDK installer. However, I cannot find any such installer inside the nRF52_SDK_0.9.0_0c82e3e.zip.

How can I install ... (more)

31k
views
55
2

## What is a client and server in BLE?

When working with BLE, one sees a lot of different names for roles, which is confusing. What is actually the difference between them all, master, slave, central, peripheral, client, server and so on?

30k
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3
2

## BLE SIG Certification, Reference design to be used to obtain EPL

Hi, does anyone know if there is a document in which is explained, by Nordic, how to obtain a bluetooth certification using nRF51822 and S110 Stack ?

I know if a reference design is strictly followed the customer do not need ... (more)

24k
views
no
no

## Can a code error prevent connection via SWD?

Is it possible that a crash in code can prevent connection by SWD to an nRF51822?

As I had an instance this morning, where after uploading, some code to a smart watch, I could no longer connect via SWD, and ... (more)

24k
views
32
11

## License for KEIL MDK is EXPENSIVE. Any way around??

I am starting my development work with Nordic Semiconductor nRF51822 Device and already purchased the Development kit. What i wanted to ask is do i need to purchase KEIL MDK 500 License to write my code/application? Because the Low ... (more)

22k
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38
9

## dealing large data packet's through ble [closed]

Hi, I need to send(using BLE) large amount of data's, which are collected by the accelerometer sensor for 1 hour. I have an external NOR flash where the accelerometer data's are stored and from there data's ... (more)

21k
views
1
vote
1

## irk as the only security perimeter [closed]

Hello, Nordic!

In our entertainment project, nrf51 based devices exclusively utilizes either central or periph. role. All of them are headless (body mounted markers, etc). The environment is hostile (in the sense, that some cheater could spoof device address, advertising ... (more)

18k
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46
2

## What low-frequency clock sources can I use?

When initializing the S110 softdevice, I can choose between the different clock sources as defined by the nrf_clock_lfclksrc_t enum:

/**@brief Possible lfclk oscillator sources. */
enum NRF_CLOCK_LFCLKSRCS
{
NRF_CLOCK_LFCLKSRC_SYNTH_250_PPM,                       /**< LFCLK Synthesized from HFCLK.                    */
NRF_CLOCK_LFCLKSRC_XTAL_500_PPM,                        /**< LFCLK crystal oscillator 500 PPM accuracy.       */
NRF_CLOCK_LFCLKSRC_XTAL_250_PPM,                        /**< LFCLK ...
(more)

17k
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no
1

## Nordic Devzone often very slow or unreachable

Hello,

lately I've often noticed problems while reaching nordic devzone, the server is often very slow and will sometimes not respond at all. Is it just me here in germany or does it happen for others too?

Marius

17k
views
5
6

## JLinkARM.dll is not correctly installed. Please run the nRF Tools installer to install the newest version. [closed]

I'm running nRFgo Studio on Windows 10. Have tried to re-install (nrfgostudio_win-32_1.21.0_installer.msi) without success.. Any idea what to do? Thanks!

16k
views
no
2

## S110 version 5.2 splitting using gcc objcopy. Programming failed at 0x10001010 [closed]

Hi 'Nordic' guys,

splitting the original S110 hex file provided by Nordic , version 5.2, there is an error extracting uicr section.

Now is only 20 bytes and not 32 as old version.

16k
views
19
4

## LDO vs DCDC (nRF51822)

I am not quite certain what the advantages/disadvantages are of using LDV vs DCDC if you are using an external regulator. In my case i use a LiPo battery outputting ~4.2V so i need to drop the voltage ... (more)

15k
views
15
5

## Can I directly start programming a nrf51822 breakout board

Hi guys, I want to know if it is possible to get started on developing applications for nRF51822 without using the evaluation kit. I want ot have a couple of breakout boards made and buy a debugger to flash the ... (more)

15k
views
35
6

## What is the power and clock model of peripheral in NRF51? [closed]

Hello,

I was puzzled by RM.

I notice POWER control register in peripheral(UART,SPI,TWI) module.

1. Will UART be powered when system power ...
(more)

15k
views
1
vote
1

As i recently wanted to have a timer as a class member and a naive

class Foo {
APP_TIMER_DEF(my_timer);
};


did not work I started to look into the source code. What I found where some very strange design decisions.

Let ... (more)

15k
views
7
4

## Hardware TWI/I2C Example

The latest TWI example I can find is from 4 SDK revisions ago and uses old libraries. Is there a sample using the nrf_drv_twi library that is recommended for current development?

15k
views
no
no

## Not answered question (nRF52 TWI easyDMA feature) [closed]

Hi,

Can anybody comment on the following question please?

https://devzone.nordicsemi.com/questi...

Thanks!

15k
views
6
4

## Compiling github projects

Hi,

After downloading any of the projects from nordic github, how does one compile the project successfully? Where should i extract the files to and what paths should i include? I have not been able to get a single project ... (more)

15k
views
25
2

## What does CCCD mean?

Dear Nordic Developer Zone,

I have a silly question. After searching in the Nordic and Bluetooth documentation, I didn't find what CCCD and SCCD mean. Theses metadata are parts of the characteristics.

Can you explain me what these acronyms ... (more)

14k
views
17
1

Concerning this:

/** @defgroup BLE_GATT_HVX_TYPES GATT Handle Value operations
* @{ */
#define BLE_GATT_HVX_INVALID               0x00  /**< Invalid Operation. */
#define BLE_GATT_HVX_INDICATION            0x02  /**< Handle Value Indication. */
/** @} */


What is the difference in a notification and indication?

14k
views
29
4

## How do I create my own service on the BLE stack? [closed]

I've sifted through the examples given to me, and none of them seem to explain how to create your own service and add it to the stack. All of the services that are registered in the ble examples (nRF51 ... (more)

14k
views
2
12

## Keil toolchain/compiler configurations incorrect

Hi all

My target board is nRF51822, and I want to run the heart rate demo project, but a error message when I compile it :

[b]Build target 'nrf51822_xxaa_s110 (256K)' assembling arm_startup_nrf51.s... arm_startup_nrf51.s: error: A3903U: Argument '--pd' not ... (more)

14k
views
no
1

Hi.

I would like to konw some ditails aboute nRF9E5 device:

1. What is the rang between 2 devices using 433 mhz.
2. do you have any samples codes ? i need to trasmitt 2 a/d data.
3. the developping board comes with ...
(more)

14k
views
6
5

## Keil - "can't load flash device description"

Just getting started with the PCA10001. I can compile if I select the device nrf51822_xxaa_s110, but when I load it tells me "can't load flash device description".

It subsequently fails to erase the flash.

Also, I noticed that when ... (more)

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• Resolved questions: 10683
• Total questions: 26151

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