Rockwell Automation 1772-AF3,D17726.5.2 User Manual AUX FUNCT PROM - Manual (Page 12)

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File Search Instruction
Chapter 3
3Ć4
Figure 3.5
Example of UserĆEntered Data (BCD)
Word Bit Location
Location 17 16 15 14 13 12 11 10 07 06 05 04 03 02 01 00 Description
0400 Not used 0 1 0 File Length = 10
0401 Available for 4 1 0 File Address, lower 3 digits
0402 Bit Storage 0 0 0 File Address, upper 3 digits
0403 Application Dependent Match word data
Instruction File Address ad Length - You can assign the file to any usable
storage location in the data table. You may want to locate the file in the middle
to upper sections of the data table (addresses 0410-0421 in Figure 3.6). Choose
a file length in accordance with your programming requirements.
Result Address - The result address is the second address that you entered into
the instruction block. It is the location of the result word (Figure 3.6). The
result word is the location where the instruction momentarily stores the position
number of the file word that matches the match word (003 in this example).
Each time the instruction finds a match, it writes the BCD bit pattern of the new
position number over the old position number in the result word. The
instruction clears the result word after setting the done bit and after the next
false-to-true transition of the enable bit.
Figure 3.6
Example Locations, Instruction File & Result Word
Word Bit Location
Location 17 16 15 14 13 12 11 10 07 06 05 04 03 02 01 00 Description
0405 0 0 3 Result Word
0410 FIrst word of Instruction File
0411
0412 Word Containing First Match (Position 003) Instruction File
(10 Words)
.
.
.
.
0421 Last Word of Instruction File