Siemens SIMATIC S7-200 System Manual page 539

transmit, 86
truncate, 101
up counter, 116
up/down counter, 116
USS protocol, 333
watchdog reset, 167
without outputs, 59
Instructions, quick reference guide, 509
Integer math instructions, example, 141
Integer to ASCII instruction, 103
example, 106
Integer to BCD instruction, 100
Integer to byte instruction, 100
Integer to double integer instruction, 100
Integral term, PID algorithm, 147
Intelligent modules, 4
CPUs that support, 323
status (SMB200 to SMB549), 493
Intercharacter timer, 91
Interface, selecting communications, 210
International standards, 392
Internet Devices, CP 243--1 IT, 219
Internet module, wizard, 462
Interrupt events
priority, 158
quick reference, 506
types, 154
Interrupt instructions
attach interrupt, 153
clear interrupt event , 153
conditional return from interrupt, 153
detach interrupt, 153
disable interrupt, 153
enable interrupt, 153
example, 159
Interrupt routines, 25, 42
calling subroutines from, 156
communication port, 156
example, 53
guidelines, 54, 155
I/O, 156
priority, 157
queues, 157
rising/falling edge, 156
sharing data with main program, 155
system support, 155
time--based, 156
types supported by S7--200, 156
understanding, 155
Interrupts
assigning to HSC, 126
high--speed counters, 120
Invert byte instruction, 161
Invert double word instruction, 161
Invert instructions, example, 161
Invert word instruction, 161
Isolation, network, 221
J
Jump instructions
jump to label, 171
label, 171
Jump to label instruction, 171
example, 171
L
L memory, 31
Label instruction, 171
LAD editor
conventions, 58
description, 56
features, 56
Ladder Logic. See LAD editor
Lamp loads, guidelines, 22
Last--in--first--out instruction, 190
example, 191
LEDs
diagnostic, 47
EM 241 Modem module, 314
Libraries, Instruction, 64
Lloyds Register of Shipping (LRS) Maritime Agency,
393
Load sequence control relay instruction, 172
Load stack instruction, 75
Loading
new current value in HSC, 131
new preset value in HSC, 131
Local I/O, 33
Local memory area (L), 31
Local variable table, 55, 63
Logic pop instruction, 75
Logic push instruction, 75
Logic read instruction, 75
Logic stack instructions
AENO, 75
AND load, 75
example, 76
load stack, 75
logic pop, 75
logic push, 75
logic read, 75
OR load, 75
Logic, control, 24
Logical connections
MPI, 215
PPI, 214
Logical operations instructions
AND, OR, XOR, 162
invert, 161
Loop control
(PID) instructions, 145–156
adjusting bias, 150
converting inputs, 148
converting outputs, 149
error conditions, 151
forward/reverse, 150
modes, 151
ranges/variables, 150
selecting type, 148
Loop inputs
converting, 148
normalizing, 148
Index
525