User manual

10
AVR1934
8413A-AVR-09/11
3 Demo application
The demo application consists of different applications selectable from a list when the
device is started:
Table 3-1. Available applications
Application name Source file Header file
Time zone application timezone.c timezone.h
Date time application date_time.c date_time.h
Production date application production_date.c production_date.h
Temperature application ntc_sensor.c ntc_sensor.h
Light sensor application lightsensor.c lightsensor.h
Backlight toggling -- --
3.1 Time zone application
When the XMEGA-A3BU Xplained
board is powered on for the first time,
the user is prompted to supply it with
the current time zone from a list of
hours from UTC -12 to UTC +12, as
well as minute offsets. The new time
zone settings are stored in EEPROM. As the UNIX timestamps generated by the RTC
is in Coordinated Universal Time (UTC), this info will be used to display the time as
local time. The time zone application is available in the date and time application
available from the main menu, and is located in
timezone.c and timezone.h
together with other time zone functionality. When the time zone application is started,
it is not possible to return to the main menu before a time zone is selected.
3.2 Date and time application
The date time application presents the user with a menu with the following options:
“Show date&time” – display local date and time in the selected time zone
“Set date” – Set the date
“Set time” - Set local time
“Set timezone” – Set time zone hour and minute offset
The menu uses the menu system, and all strings and options are defined at the top of
date_time.c. This function handles calling the correct application based on the
user’s choice in the menu. If the back
button is pressed, the user will return
to the main menu.
The “Show date&time” application
shows the current local date and time,
computed from the RTC UNIX
timestamp. Note that this time will not be completely accurate, due to inaccuracies in
the RTC.
Fi
g
ure 4 Date&time menu
Figure 3 Timezone selection