Applies To:
  • CitectSCADA 5.31, 5.40, 5.41, 5.42, 5.50, 6.0, 6.1, 7.0
  • CitectHMI 5.31, 5.40, 5.41, 5.42, 5.50, 6.0, 6.1, 7.0
  • CitectFacilities 5.31, 5.40, 5.41, 5.42, 5.50, 6.0, 6.1, 7.0
Summary:

How can I display the status of each of the individual bits which make up an unsigned integer?

 

Solution:

The logic operator which will mask everything but the required bit is 'BITAND'.  In a real world project it would be best to create a digital tags on a disk device in the project and run an event to update the digital tags with values from the integer on a regular basis.  That will provide a single location for the conversion code should any changes need to be made in the future.

Example:

Expression = Tag1 BITAND 0xXX

where:

Tag1 is an unsigned integer, and

Bit of Int Decimal Mask Hexadecimal Mask
Bit0 2^0 = 1 0x1
Bit1 2^1 = 2 0x2
Bit2 2^2 = 4 0x4
Bit3 2^3 = 8 0x8
Bit4 2^4 = 16 0x10
Bit5 2^5 = 32 0x20
Bit6 2^6 = 64 0x40
Bit7 2^7 = 128 0x80
Bit8 2^8 = 256 0x100
Bit9 2^9 = 512 0x200
Bit10 2^10 = 1024 0x400
Bit11 2^11 = 2048 0x800
Bit12 2^12 = 4096 0x1000

Bit13

 2^13 = 8192 0x2000
Bit14 2^14 = 16384 0x4000
Bit15 2^15 = 32768 0x8000

Note: This should only be used for reading from a PLC or integers in the PLC which will only be writen by Citect.  That is because writting a change to a single bit will write the Citect values to all the bits.
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