ANT Forum

Hi everyone,

I am brand new to this community and came across ANT technology whilst choosing my final project as an engineer, so my questions are very noob.

I am looking to develop a datalogger for a cyclist, and want to recieve data from a power meter and speed & cadence meter. Unfortunately the university budget is quite tight for students going out and buying tech for their projects. So my questions:

1. Can I control a sparkfun nRF52 breakout board with an arduino with an SD card to log the data. I have some familiarity with arduino, and as it is a cheap platform would like to go down that route if the libaries are suitable for my project.

2. What is the minimum hardware that I would need to allow my breakout board (or something else depending on suggestions) to recieve and store the data from the power and speed & cad sensors?

3. Finally despite the fact I have been over all the documentation, I am reading it with the eyes of a mechanical engineer who is not familiar with all therminology. That being said I would appreciate a few steps I could follow to getting started on recieving data from a given sensor and very laymans temrs of what the the uses of the different softwares are for.

I realise these are very basic questions and I don't want someone to hold my hand through the whole process, its just that after reading the documentaion I am still a bit unsure how to proceed and what the minimum hardware I would need to invest in to get to the data logging stage.

Many thanks in advance to anyone that can offer some suggestions.

Darian      

1. Any nRF52 based device should be able to run ANT as long as it has a 32.768 kHz crystal with +/- 50PPM or better accuracy. If you're planning to interface it with Arduino as an external network processor, you will need your own UART drivers to interface using the Network Protocol Serial Interface spec. I've seen one project pop up on the forum recently (https://www.thisisant.com/forum/viewthread/6531/) but I haven't had a look at it myself yet.

2. Technically you could use the nRF52 as a standalone SoC without the Arduino, but it would require familiarity with C and embedded programming. This also depends on how much data you need to store. Each sensor transmits 8 bytes about 4 times a second, storing this data stream raw might not be a good idea depending on how many sensors you're recording from and for how long. The nRF52832 has 512 kB of flash, but around 1/3 of that will be taken up by your application code and the S212 SoftDevice. Arduino's come in many sizes.

3. If this device cannot be Android or PC based, then you should get familiar with embedded development and some ANT/ANT+ basics. SimulANT+ and ANTware are PC tools meant to assist with the development of the ANT/ANT+ wireless messages. SimulANT+ can accurately emulate ANT+ sensors/displays, while ANTware is used to play with generic ANT channels.

If you could use the PC/Android tools, it could be as simple as plugging a USB stick into the device and using SimulANT+ or ANT+ Plugins on Android to decode the sensor data for you. Typically this is where most developers start or do their sanity checks on, but you'd need an ANT USB stick.

Also, it doesn't look like that breakout board has a JTAG programmer. You'll need to already have one yourself. If you didn't mind the cost, the D52DK2 has all of the parts you'd need to get started.      

Thank you for the reply, I have decided to take your advice and purchase the develpoment kit. I am also going to look in to maybe using a raspberry pi instead of arduino. I am sure I will have other questions down the line. Thanks for the advice for getting going.      

My first two home made bike computers were both AVR based. Second one was a mega128 I think. It came on a board with built in sd card and 40 odd IO's. As well as an serial ANT board there was, GPS and a pressure sensor, 2 lcd's, 2 buttons and a quadrature style knob for control and a number of other external bits and pieces.

Interfacing to all this stuff is straight forward and possible if you know what your doing but the fact the data space was only 8k meant you could not do anything fancy filtering on any data just grab it and format it to the sd-card. No OS's involved here just straight to the metal programming. There was a good library dealing with the SD card that I was using that kept me away form the complexity there.

So it is possible but it would be easier with something higher end with more code space and ram and readily available code for the more complex bits.

I have managed to get an 8 pin 8k code space AVR already build into an LED light driver to interface to an ANT board over a serial interface while still being able to act as the light controller but under ANT control.