Adafruit NRF52840 Feather Express

Availability:

3 in stock


This board enables connecting buttonsswitchesencoders, potentiometers,  rotary switchesjoysticks  and various sensors, to easily deploy wireless solutions.

An battery charging circuit allows you to power the board with a battery for embedded applications, along with an internal connexion in order to measure precisely the battery voltage, so you will know the charge that’s left.

25,75  incl. VAT (21,46  excl. VAT)

Bodac

Le Bodac est un montage qui permet de mettre en oeuvre plusieurs boutons sur une seule entrée analogique, tout en ayant la possibilité de les avoir appuyés en même temps. Le montage est simple : une résistance entre chaque borne des boutons, et un seul fil entre chaque bouton.

Ce pack de résistances de précision 1%, permet de réaliser un Bodac pour 5 boutons ou moins.

Led de charge
IO Headers

Les supports IO permettent d'éviter de souder directement sur la carte, évitant ainsi les courts-circuits. Vous pourrez connecter vos boutons/encodeurs/etc avec des câbles dupont. La carte sera fournie avec les supports déjà soudés.

Firmware

En choisissant un package NodeBlue, vous bénéficiez de la configuration de votre choix. Un formulaire de configuration vous sera envoyé après votre commande afin de préciser la programmation souhaitée. Ce formulaire est similaire à cette page, qui permet de tester si la configuration est possible. La carte sera programmée et testée en conséquence, et les schémas de câblage vous seront fournis. Si vous ne prenez pas de package, vous devrez programmer la carte vous même avec l'IDE Arduino. Plus d'information sur les différences entre le package standard et le package pro sont disponibles sur cette page.

3 in stock

You will have access to 22 I/Os, including 7 analog inputs with a 12 bits ADC. One additional digital input is available for the on board user switch, as well as an “NFC” pad under the board if another input is needed. The inputs are 3.3 V and are not 5 V tolerant. The heart of this board is the NRF52840, the most suitable microcontroller on the market for embedded systems. Clocked at 64 MHz, it also offers 2 SPI ports, 1 I2C port , and 1 serial port. Like on all the boards we propose, we have enhanced the kernel in order to offer as much features as possible.

Note : If you need anything else than inputs (leds, Nextion screen, etc), you will have to use a NrfDongle dongle.

Drivers Download : Adafruit Drivers

SKU: 357 Category:
Weight 0,02 kg
Dimensions 1 × 1 × 1 cm

Schematics

Pinout

 

Default program :

Tutorials

Axis Calibration
To reprogram the board or to calibrate the axis, you need to install Node Blue. It is recommended to reprogram the board to benefit from the latest version.
Depending on the project you are using, you will have to use one of the following 2 methods:
  • Calibration with the serial monitor
You will need to have a  “NodeBlue Interface”, “SimHub Interface” or “Nextion Interface” module in your project.
Attention : if the USB port is used for a Nextion, leds or other Simhub interfaces, you’ll need to disconect SimHub in order to free the serial COM port.
In Node Blue, open a serial monitor on the board (at the top of the window, select the correct COM port and click on the # icon), You can see the calibration messages in the serial monitor (window at the bottom in Node Blue). You must also display the “Controllers” tab at the top right. Select “Raw” as display mode.
For each axis:
  • Click on the “Cal” input of the analog input module, the sensor module (eg AS5600) or the “Range” module. The module name can be “Accel”, “X”, “Y” or “Z”, or something else depending on the application. Once cal is pressed, a message appears in the serial monitor window. Follow the instructions.
  • Once the calibration is complete, double click on the module to change the low and high deadband parameters. Check in the controller tab that when the axis is completely released the value is 0 and when it is fully released the value is 65535. Adjust the dead zones if necessary. Click on “Invert” if you need the axis to work in an inverted way.
Once the calibration of all axis is complete, save the project so that the settings are saved, either by using the “Save project” menu or with the CTRL-S key combination. If the project is read-only, use the “Save As” menu and choose another name.
  • Manual Calibration (if the USB Virtual serial port is not present or used by another non compatible module)
In the “Controllers” tab at the top right. Select “Raw signed” as the display mode.
For each axis:
  • Double-click on the analog input module “X”, “Y” or “Z” (or any other name depending on the project) concerned by the axis.
  • Position the axis to the minimum, copy the value displayed in the controller tab (adding a small margin), in the “In Min” parameter of the module.
  • Position the axis to the maximum, copy the value displayed in the controller tab (by removing a small margin), in the “In Max” parameter of the module.
  • change the low and high deadband parameters. Check in the controller tab that when the axis is completely released the value is 0 and when it is fully released the value is 65535. Adjust the dead zones if necessary.

 

Once each axis has been done :

  • Save the project so that the settings are saved, either by using the “Save project” menu or with the CTRL-S key combination. If the project is read-only, use the “Save As” menu and choose another name.
  • Select the com port among those detected (disconnect any other detected boards to be sure to program the board you want).
  • Upload the project to the board (“Upload” button).

 

The settings are saved in the flash memory of the board and are restored at each restart.

Dimensions

SHOPPING CART

close