1766-RM001A-EN-P MicroLogix 1400 Programmable Controllers ...

Number Systems 665Hex MaskThis is a 4-character code, entered as a parameter in SQO, SQC, and otherinstructions to exclude selected bits of a word from being operated on bythe instruction. The hexadecimal values are used in their binaryequivalent form, as indicated in the figure below. The figure also showsan example of a hexadecimal code and the corresponding mask word.HexValue0123456789ABCDEFBinaryValue0000000100100011010001010110011110001001101010111400110111101111Hex Code0 0 F F0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1Mask WordBits of the mask word that are set (1) will pass data from a source to adestination. Reset bits (0) will not. In the example below, data in bits 0-7of the source word is passed to the destination word. Data in bits 8-15 ofthe source word is not passed to the destination word.Source Word 1 1 1 0 1 0 0 1 1 1 0 0 1 0 1 0Mask Word 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1Destination Word 0 0 0 0 0 0 0 0 1 1 0 0 1 0 1 0(all bits 0 initially)Publication 1766-RM001A-EN-P - October 2008