Sportident stations for connecting to your PC are available with either a serial ( RS232 ) or USB interface. At some of our events we have up to 3 stations on the table for registration and download, so all those cables quickly get ugly. Software to suit tablet and phones is also becoming more readily available for orienteering. Using wireless would be a way to connect the Sportident stations easily to these devices.
This article will explain one way of getting your sportident station to connect via a wireless Bluetooth connection. I have purposely used standard off the shelf parts so they can be easily sourced. The adapter is fairly simple to put together though some soldering and assembly skills are necessary. The main parts can be purchased from adafruit.com and sparkfun.com. Some resellers such as nicegear.co.nz here in New Zealand also sell items from both suppliers. The adapter will have a range of about 10 metres, so it’s not really suitable to create a radio control, but then that’s what O-Lynx is for.
Note: According to the Adafruit docs, this solution doesn’t work with iOS devices. Also Sportident Config and Config Plus seem to have trouble locating the Bluetooth port. O-Lynx software as well as the OE range of software all work fine, as should most software.
The finished adapter is not only suitable for Sportident stations. It should be able to be used with any serial device e.g. barcode scanners, printers etc.
Parts List.
- Plox 6000mAh USB Power Pack or similar
- SparkFun USB Micro breakout , BOB-12035
- SparkFun MAX3232 Breakout, BOB-11189
- Adafruit Bluefruit EZ-Link, 1588
- Adafruit Perma Proto Half Size, 1609
- Breakaway Header – Straight e.g. Sparkfun PRT-00116 or Adafruit 2691
- DB9 Male connector
- On/Off switch
- Sportident BSF7 Serial station
Description.
This bluetooth adapter is based around the Bluefruit EZ-Link board which is a really nice Serial-to-Bluetooth convertor with automatic everything. Just wire it up correctly and it will work. The other parts all just play a supporting role. I chose to use a commercial USB power pack to provide power for the adapter though solutions like the Adafruit Powerboost and a LiPo battery could also be used. The best thing about the USB Power pack is that it provides a simple way to get an indication of the batteries charge. Shake the USB Power Pack and its 4 lights indicate the state of charge. The other main item is the MAX3232 breakout which converts the serial voltage levels to values suitable for the EZ-Link. The micro USB breakout is used simply as a convenient way to connect the Power pack. Some of the photos show an additional push button connected to the EZ-Link’s “pair” button, but this proved unnecessary.
Connection details are shown here….
or download Serial to Bluetooth.pdf
Full details on the Adafruit EZ-Link, including pairing with your device are available at..
https://learn.adafruit.com/introducing-bluefruit-ez-link
Apart from the Power Pack and enclosure, parts work out at about US $35.
Putting electronics in a box is always the hardest part of any build. To get a low profile I used a sandwich type build with 2mm and 15mm custom wood glued together along with a 3mm smoked acrylic top so the LED’s would be visible. The 165 x 125 x 15mm custom wood mid-section was cut out with a band saw, fret saw and filed to match the components. Lastly a BSM7 mount was fitted to the top for the station. When fitting these Sportident mounts, it’s important to have a gap between whatever it’s mounted on and the mount itself. The mount must be able to flex to get the stations on and off. Any variety of alternative box such as one of the many ready made plastic enclosures could also be used to put the adapter in.
