S7 1200 DB to store a bit

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Hello,

I have a signal from a switch on my PLC. The signal is either 1 or 0. i want to store the current value of the switch in a DB block.

I have currently set up a DB to store a DWord and it works fine. However when i set up a new DB to store the switch signal i was not successful. Do i use the data type as "Bool" in the DB block?

Also I cannot use a MOVE block to move the 1 or 0 signal to the DB? Any help would be much appreciated

 

[Mike_RH]

Yes to store the state of a bit, you need a bool data type in the DB.
A MOV is used to a move a byte, word or dword not a bit. To move a bit use the bit level instructions.

 

[BryanG]

You might want to look at using M memory rather than DB memory for 'bit' signals. Then you won't need a 'Move' instruction you will just to a contact to operate a coil. The lower values in M memory can be made retentive if needed.