About basic instructions – Rockwell Automation 1761-HHP-B30 MicroLogix 1000 with Hand-Held Programmer (HHP) User Manual
Page 121
Chapter 8
Using Basic Instructions
8–2
Branch Instructions
Mnemonic
Function
Code
Name
Purpose
Page
MPS
10
Memory Push
Stores the rung state that is present immediately preceding the MPS instruction.
8–10
MRD
11
Memory Read
Reads the rung state stored by the MPS instruction and resumes operation using
that rung state.
8–10
MPP
12
Memory Pop
Removes the rung state stored by the MPS instruction, reads it, and resumes
operation using that rung state.
8–10
ANB
13
And Block
Places two blocks of logic in series with each other (ANDs them).
8–12
ORB
14
Or Block
Places two blocks of logic in parallel with each other (ORs them).
8–12
Timer/Counter Instructions
Mnemonic
Function
Code
Name
Purpose
Page
TON
0
Timer-On Delay
Counts timebase intervals when the instruction is true.
8–16
TOF
1
Timer-Off Delay
Counts timebase intervals when the instruction is false.
8–18
RTO
2
Retentive Timer
Counts timebase intervals when the instruction is true and retains the
accumulated value when the instruction goes false or when power cycle occurs.
8–20
CTU
5
Count Up
Increments the accumulated value at each false-to-true transition and retains the
accumulated value when the instruction goes false or when power cycle occurs.
8–24
CTD
6
Count Down
Decrements the accumulated value at each false-to-true transition and retains
the accumulated value when the instruction goes false or when power cycle
occurs.
8–25
RES
7
Reset
Resets the accumulated value and status bits of a timer or counter. Do not use
with TOF timers.
8–27
Basic instructions are used most commonly for relay replacement functions,
counting, and timing operations. These instructions, when used in
Instruction List (Boolean) programs, represent hardwired logic circuits used
for the control of a machine or equipment.
The basic instructions are separated into four groups: bit, branch, timer, and
counter. Before you learn about the instructions in each of these groups, we
suggest that you read the overview that precedes the group:
•
Bit Instructions Overview
•
Branch Instructions Overview
•
Timer Instructions Overview
•
Counter Instructions Overview
About Basic Instructions