General description
To eliminate loss of critical information (state of the controller, external devices status, and so on..) I case of power reset , CANNY7 controller equipped with non-volatile memory. The values saved in EEPROM will be available in special registers after the power is restored.
There are 64 16-bit non-volatile memory cells, which are accessed by corresponding read and write registers.
| Note:
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Working with non-volatile memory does not require any special pre-configuration.
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Nonvolatile memory registers
Below is a description of permissible values of controller nonvolatile memory setup registers. They are used to store information in the NVRAM cells.
| Address
|
Expected values
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| EEPROM Set Cell 00
|
| ...
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| EEPROM Set Cell 63
|
|
| 0...65535
|
=
|
stored value.
|
|
Below is a description of acceptable values controller non-volatile memory read registers. They are used to restore information from the NVRAM cells.
| Address
|
Return values
|
| EEPROM Get Cell 00
|
| ...
|
| EEPROM Get Cell 63
|
|
| 0...65535
|
=
|
stored value.
|
|
Examples
An example of a functional diagram with non-volatile memory cells.
The number of keystrokes connected to channel No. 0 of the controller is summed with the value of the "counter" previously stored in the named network. At the moment of releasing the buttons, the value of the network "counter" of memory in cell No. 0 of the controller's non-volatile memory. After the controller power is turned off and restored, the value stored in the nonvolatile memory cell reads and transfers the value back to the named network counter. Thus, in order to avoid the loss of information on the number of operations to cut off electricity.
| Note:
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The process of storing data in the NVRAM takes time, i.e. not instantaneous.
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| Note:
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The number of overwrites information in non-volatile memory is limited. CANNY 7 memory operation driver is organized in such a way that substantially increased its resource. However, avoid permanent unwanted data saving in to the NVRAM or store data on each execution cycle of the diagram. Perform information preservation upon a certain condition (see example above).
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See also
CANNY 7
CANNY 7, User Preprogrammed Parameters
