Very quick update for something that’s been a lot of work: you’ll find a new version of the Android App available for download in the Google Play Store. A new version of the iOS app is awaiting Apple approval (but has been released to the beta group). The app itself is almost identical, but they are linked to a new version of firmware which you can upload to you Mooshimeter (more on that procedure here).
- Logging can now be started and stopped while your smartphone and Mooshimeter are connected
- Every sample that is sent over the air while connected is logged to the SD card, so you can look later and see everything you did with the Mooshimeter
- If you change the settings of your Mooshimeter while logging, a new title row will appear in the log file
- The Mooshimeter supports a wider variety of SD cards
- The official specs haven’t changed but users were reporting issues with specific models/manufacturers of SD cards. The new firmware is more permissive and most of those issues are resolved.
- Battery life while in connection improved
To get around the timing issues of talking to an SD card while maintaining a radio connection with a single processor (the CC2540) and no operating system I implemented threads with the standard library setjmp.h routines and some manipulation of the stack pointers. Since the 8051 has stacks in 3 different memory spaces this was a pain. I think this technique will be generally useful to others in similar predicaments, I’ll do a technical write-up on it soon.