DL06 Micro PLC User Manual, 3rd Edition, Rev. E
5-153
Chapter 5: Standard RLL Instructions
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A
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D
Step 1: Load the length of the table (number of V-memory locations) into the first level of
the accumulator stack. This parameter must be a HEX value, 0 to FF.
Step 2: Load the starting V-memory location for the table into the accumulator. (Remember,
the starting location of the table blank is used as the table pointer.) This parameter must be
a HEX value.
Step 3: Insert the RFB instruction which specifies destination V-memory location (Vaaa).
Helpful Hint:
— For parameters that require HEX values when referencing memory locations,
the LDA instruction can be used to convert an octal address to the HEX equivalent and load
the value into the accumulator.
Helpful Hint:
— The instruction will be executed every scan if the input logic is on. If you
do not want the instruction to execute for more than one scan, a one-shot (PD) should be
used in the input logic.
Helpful Hint:
— The pointer location should be set to the value where the table operation
will begin. The special relay SP0 or a one-shot (PD) should be used so the value will only be
set in one scan and will not affect the instruction operation.
NOTE: Status flags (SPs) are only valid until another instruction that uses the same flag is executed
or the end of the scan The pointer for this instruction can be set to start anywhere in the table. It is
not set automatically. You must load a value into the pointer somewhere in your program.
aaa
A
R F B
Operand Data Type
DL06 Range
A
aaa
V-memory
V
See memory map
Discrete Bit Flags
Description
SP56
On when the table pointer equals zero..
DS
Used
HPP Used
Remove from Bottom (RFB)
The Remove From Bottom instruction moves a value from
the bottom of a V-memory table to a V-memory location and
decrements a table pointer by 1. The first V-memory location
in the table contains the table pointer which indicates the
next location in the table to be moved. The instruction will
be executed once per scan provided the input remains on.
The instruction will stop operation when the pointer equals
0. The function parameters are loaded into the first level of
the accumulator stack and the accumulator by two additional
instructions. Listed below are the steps necessary to program the
Remove From Bottom function.