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Data Shift Instructions Section 3-9
Description When the execution condition of the shift input bit (bit 14 of C) changes to ON,
all the data from St to E is moved in the designated shift direction (designated
by bit 12 of C) by 1 bit, and the ON/OFF status of the data input is placed in
the rightmost or leftmost bit. The bit data shifted out of the shift register is
placed in the Carry Flag (CY).
Flags
Precautions The above shift operations are applicable when the reset bit (bit 15 of C) is set
to OFF.
When reset (bit 15 of C) turns ON all bits in the shift register, from St to E will
be reset (i.e., set to 0).
When St is greater than E, an error will be generated and the Error Flag will
turn ON.
Examples Shifting Data
If shift input CIO 030014 goes ON when CIO 000000 is ON, and the reset bit
CIO 030015 is OFF, words CIO 0100 through CIO 0102 will shift one bit in the
direction designated by CIO 030012 (e.g., 1: Right) and the contents of input
bit CIO 030013 will be shifted into the rightmost bit, CIO 010000. The con-
tents of CIO 010215 will be shifted to the Carry Flag (CY).
Index Registers ---
Indirect addressing
using Index Registers
,IR0 to ,IR15
–2048 to +2047, IR0 to –2048 to +2047, IR15
DR0 to DR15, IR0 to IR15
,IR0+(++) to ,IR15+(++)
,–(– –)IR0 to, –(– –)IR15
Area C St E
St
E
E
St
Shift direction
Data input
Data input
Name Label Operation
Error Flag ER ON when St is greater than E.
OFF in all other cases.
Carry Flag CY ON when 1 is shifted into it.
OFF when 0 is shifted into it.
OFF when reset is set to 1.
C: 0300
C
E
St
Data input:
CIO 030013
Reset input bit: 0
Shift input bit: 1
Shift direction
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