Publication 1762-RM001C-EN-P
12-2 Logical Instructions
Addressing Modes and File Types can be used as shown in the following
table:
Updates to Math Status
Bits
After a logical instruction is executed, the arithmetic status bits in the
status file are updated. The arithmetic status bits are in word 0 bits 0-3 in
the processor status file (S2).
Table 12.1 Logical Instructions Valid Addressing Modes and File Types
For definitions of the terms used in this table see Using the Instruction Descriptions on page4-2.
Parameter
Data Files
Function Files
(1)
(1) DAT files are valid for the MicroLogix 1500 only. PTO and PWM files are valid for MicroLogix 1200 and 1500 BXB
units.
CS - Comms
IOS - I/O
DLS- Data Log
(2)
(2) The Data Log Status file can only be used by the MicroLogix 1500 1764-LRP Processor.
Address
Mode
(3)
(3) See Important note about indirect addressing.
Address
Level
O
I
S
B
T, C, R
N
ST
L
MG, PD
RTC
HSC
PTO, PWM
STI
EII
BHI
MMI
DAT
TPI
Immediate
Direct
Indirect
Bit
Word
Long Word
Element
Source A •••••• ••••••••••••••• • •••
Source B
(4)
(4) Source B does not apply to the NOT instruction. The NOT instruction only has one source value.
•••••• ••••••••••••••
• • •••
Destination •••••• ••• ••• •
• •••
IMPORTANT
You cannot use indirect addressing with: S, ST, MG, PD,
RTC, HSC, PTO, PWM, STI, EII, BHI, MMI, DAT, TPI, CS,
IOS, and DLS files.
Table 12.2 Math Status Bits
With this Bit: The Controller:
S:0/0 Carry always resets
S:0/1 Overflow always resets
S:0/2 Zero Bit sets if result is zero, otherwise resets
S:0/3 Sign Bit sets if result is negative (MSB is set), otherwise resets
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