MicroLogix 1000: specifying indexed addresses
The indexed address symbol is the # character. Place the # character immediately before the file-type identifier in a logical address. You can use more than one indexed address in your ladder program.
Enter the offset value in word 24 of the status file (S:24). All indexed instructions use the same word S:24 to store the offset value. The processor starts operation at the base address plus the offset. You can manipulate the offset value in your ladder logic before each indexed address operation.
IMPORTANT:
Instructions with a # sign manipulate the offset value stored at S:24. Make sure you monitor or load the offset value you want prior to using an indexed address. Otherwise, unpredictable machine operations could occur with possible damage to equipment and/or injury to personnel.
When you specify indexed addresses, follow these guidelines:
- Make sure the index value (positive or negative) does not cause the indexed address to exceed the file type boundary.
- When an instruction uses more than two indexed addresses, the processor uses the same index value for each indexed address.
- Set the index word to the offset value you want immediately before enabling an instruction that uses an indexed address.
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