You can only use the data type BIT for individual variables within structures or function blocks. The possible values are TRUE (1) and FALSE (0).

A BIT element requires 1 bit of memory space, and you can use it to address individual bits of a structure or function block using its name. BIT elements, which are declared sequentially, are consolidated to bytes. This allows you to optimize memory usage compared to BOOL types, which each occupy at least 8 bits. However, bit access takes significantly longer. Therefore, you should only use the data type BIT if you want to define the data in a specified format.

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