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The register storage class defines local variables that should be stored in a register or registers rather than in RAM. It is used as follows:

register data-type name <[>= value<]>;


data-type is the data type of the variable.
name is the name of the variable.
value is the value to assign to the variable.

In general, the Cx51 Compiler ignores the register storage class. All variables are stored in registers if and when possible.


  • The register storage class may be used only inside a function definition.
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