Timer

A simple Timer interrupt library for nRF52 in Arduino.

Abstract

This repository is a part of the HiveTracker project, a miniaturization of the Vive Tracker by HTC. It allows sub-millimetric 3d positioning, and embeds a 9DoF IMU with sensor fusion. This project is open source, all the materials can be found online:

https://hivetracker.github.io

This repository only contains the Arduino code about Timer imterruptions. To program it, more explanations are below:

Install

The processor used in this project is not Arduino compatible by default but the following steps explain how to do it anyway.

1. Download the Arduino IDE:

https://www.arduino.cc/en/Main/Software

2. Install the nRF52 support - read carefully these instructions:

https://github.com/sandeepmistry/arduino-nRF5#installing

Compile

In the "Tools" menu select:

• "Board->Generic nRF52"
• "Softdevice->S132" (select "None" if you don't use BLE)
• "Pinout->Custom"

Program

Probes

This board doesn't come with a programmer for now but several cheap solutions exist:

1. Adafruit sells J-Link and ST-Link probes:

https://www.adafruit.com/product/3571

https://www.adafruit.com/product/2548

2. For those with limited budget, these alternatives work too:

https://www.aliexpress.com/item/1PCS-ST-LINK-Stlink-ST-Link-V2-Mini-STM8-STM32-Simulator-Download-Programmer-Programming-With-Cover/32839270086.html

https://www.aliexpress.com/item/1PCS-Jlink-for-SWD-Jlink-3-Wire-for-STM32-on-SWD-Debug-New/32746364818.html

3. But if you already have a Teensy or a 3.3V Arduino compatible board with ATmega32U4 (such as this one), you can build your own programmer thanks to this repository:

https://github.com/myelin/arduino-cmsis-dap

Setup

The above Install section should be enough in most cases but you might need to install udev rule on linux:

https://raw.githubusercontent.com/arduino/OpenOCD/master/contrib/60-openocd.rules

Finally, in the "Tools" menu select the right SWD probe:

• "Programmer->J-Link"
• "Programmer->ST-Link"

Enjoy!