Ready to test threshold alert functions.
Ready to test hysteresis and resolution functions.
Updated.
Tested OK.
Thresholds tested OK.
Changed alert pin.
Refactored threshold functions.
Added function to clear interrupt.  Not tested.
Updates.
Updates.  Not tested.
Updates.
Fixed incorrect hysteresis functions.  Tested OK with positive upper threshold.
Change resolution for testing.
Tested OK with positive upper and lower thresholds.  Fixed problem with handling out of range at startup.  Now modified to test with negative lower threshold
Tidied up code.
Testing negative threshold.
Fixed bug in getHysteresis.  Small changes to example program.  Tests OK but reveals potential issue with hysteresis descending through Tlower.
Updated getTaFloat to use resolution instead of #define number of binary places.  Added comments about hysteresis and thresholds.  Renamed test #defines.