Installation manual

Publication 1747-RM001G-EN-P - November 2008
5-26 Data Handling Instructions
Effects on Index Register S:24
The value present in S:24 is overwritten with the position value when a
false-to-true transition of the FFL/FFU or LFL/LFU rung occurs. For the
FFL/LFL, the position value determined at instruction entry is placed in S:24.
For the FFU/LFU, the position value determined at instruction exit is placed
in S:24.
When the DN bit is set, a false-to-true transition of the FFL/LFL rung does
not change the position value or the index register value. When the EM bit is
set, a false-to-true transition of the FFU/LFU rung does not change the
position value or the index register value.
FIFO Load (FFL) and FIFO
Unload (FFU)
FFL and FFU instructions are used in pairs. The FFL instruction loads words
into a user-created file called a FIFO stack. The FFU instruction unloads
words from the FIFO stack, in the same order as they were entered.
Instruction parameters have been programmed in the FFL-FFU instruction
pair shown on page 5-27.
EN
DN
EM
FFL
FIFO Load
Source N7:69
FIFO #N7:76
Control R6:0
Length 48<
Position 0<
FFL
EU
DN
EM
FFU
FIFO Unload
FIFO #N7:76
Dest N7:70
Control R6:0
Length 48<
Position 0<
FFU
Output Instructions
Fixed SLC
5/01
SLC
5/02
SLC
5/03
SLC
5/04
SLC
5/05
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