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19.6 Saving data on the device 171
19.6.1 Creating user data entries
19.6.1.1 Basics about user data
It is possible to save arbitrary user specific data on the hardware's non-volatile memory. The amount of possible
entries depends on the length of the individual entries as well as the size of the devices non-volatile memory
reserved for storing:
• mvBlueFOX,
• mvBlueFOX-M,
• mvBlueFOX-MLC,
• mvBlueFOX3, and
• mvBlueCOUGAR-X
currently offer 512 bytes of user accessible non-volatile memory of which 12 bytes are needed to store header
information leaving 500 bytes for user specific data.
One entry will currently consume:
1 + <length_of_name (up to 255 chars)> + 2 + <length_of_data (up to 65535 bytes)> + 1 (access mode) bytes
as well as an optional:
1 + <length_of_password> bytes per entry
if a password has been defined for this particular entry
It is possible to save either String or Binary data in the data property of each entry. When storing binary data
please note, that this data internally will be stored in Base64 format thus the amount of memory required is 4/3
time the binary data size.
The UserData can be accessed and created using wxPropView (p. 77) (the device has to be closed). In the section
"UserData" you will find the entries and following methods:
• "CreateUserDataEntry"
•
"DeleteUserDataEntry"
• "WriteDataToHardware"
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