Usage Precaution - Denso BHT-1400QWB-CE Software User Manual

1.3. Usage Precaution

 Data backup
Non-volatile memory (flash memory) is used to store user data for the BHT. Flash memory has a finite number
of program-erase cycles, therefore frequent access concentrated on the specific memory area may lead to data
loss.
To optimize the Flash memory usage, the wear leveling function, which automatically distributes data evenly
over the flash memory, is implemented for the BHT.
Nevertheless, backing up important data is strongly recommended in order to prepare for unexpected data
loss.
 Flash memory
Flash memory reaches the end of its lifetime as the number of writes increase. Application development must
follow the restrictions listed below in order to prolong the flash memory lifetime.
- Limit the data size written in the flash memory to maximum 100 M bytes per day.
- Limit the write cycles to maximum 5,000 times per day for data smaller than 8 k bytes.
 RAM memory
All data including files and settings stored in the RAM will be lost and the RAM will revert to the factory default;
- If the BHT is left for a long period with the battery removed,
- If the BHT is left with the dead battery,
- If the battery is incorrectly replaced,
- When Performing full reset. (Refer to "3.3 Reset and Full Reset")
Back up any important data to the "Flash" folder or to the computer before full reset. The BHT performs a full
reset when the BHT turns ON after the data in the RAM is deleted.
Using the backup and auto-setup tools provided by the BHT are recommended in order to reduce the risk of
data loss. Refer to "2 Setup" for details of these tools.
 Ensuring stable operations
Windows CE may cause memory leaks when used over long periods.
Resetting the BHT regularly utilizing the application created (once a day etc.) or as daily routine is
recommended for ensuring stable BHT operation.
For example, call a reset task utilizing the application at the end of daily work or at scheduled update.
Refer to the BHT API Reference Manual or the BHT Class Library Reference Manual for how to program a
reset task.
 SD card
The microSD card will not be accessible for short periods of time when the BHT is turned OFF and back ON
again (or suspend and resumed) while the application is running.
The application deployed in the microSD card may not continue the process correctly if the application
accesses the microSD card during these periods. Reset the BHT if the application freezes or the LED indicator
stays blue.
To prevent the problem, copy the application to the built-in Flash memory before executing the application if the
application is deployed in the microSD card,
 Application debugging using Windows Error Reporting
Enable Error Reporting function in the Control panel when developing applications (recommended).
Using Windows CE Dump Viewer in a host computer is also recommended in order to detect and solve
application problems as early as possible.
Refer to "5.2 Error Reporting" for details.
- 3 -