A–B
23
Chapter
23–1
Bit Shift, FIFO, and LIFO Instructions
This chapter covers instructions for use with fixed, SLC 5/01, and SLC 5/02
processors:
•
Bit Shift Left (BSL)
•
Bit Shift Right (BSR)
These are output instructions that load data into a bit array one bit at a time.
The data is shifted through the array, then unloaded one bit at a time.
Bit shift instructions are useful in conveyor applications and product
evaluation (pass/fail) applications.
Instructions for use with SLC 5/02 processors only:
•
FIFO Load and Unload (FFL, FFU)
•
LIFO Load and Unload (LFL, LFU)
FIFO instructions provide a method of loading words into a file and
unloading them in the same order as they were loaded. First word in is the
first word out.
LIFO instructions provide a method of loading words into a file and
unloading them in the opposite order as they were loaded. Last word in is
the first word out.
FIFO and LIFO instruction applications include assembly/transfer lines,
inventory control, and system diagnostics.
All application examples shown are in the HHT zoom display.
The following general information applies to bit shift, FIFO, and LIFO
instructions.
Effect on Index Register in SLC 5/02 Processors
All of the instructions in this chapter alter the contents of the index register,
S:24. Details appear with the specific instructions.
Bit Shift, FIFO, and LIFO
Instructions Overview
