Inhaltsverzeichnis • v
WAGO-I/O-SYSTEM 750
ETHERNET TCP/IP
4.1.2.2 Netzwerk-Topologie.....................................................................76
4.1.2.3 Koppelmodule...............................................................................78
4.1.2.4 Wichtige Begriffe..........................................................................79
4.1.3 Netzwerkkommunikation ..................................................................81
4.1.3.1 Protokoll-Schichtenmodell (Beispiel)...........................................81
4.1.3.2 Kommunikationsprotokolle ..........................................................83
4.1.3.2.1 ETHERNET..................................................................................84
4.1.3.2.2 IP-Protokoll...................................................................................85
4.1.3.2.3 TCP-Protokoll...............................................................................90
4.1.3.2.4 UDP...............................................................................................91
4.1.3.2.5 ARP...............................................................................................91
4.1.3.3 Verwaltungs- und Diagnoseprotokolle.........................................92
4.1.3.3.1 BootP (Bootstrap Protokoll) .........................................................93
4.1.3.3.2 HTTP (HyperText Transfer Protokoll).........................................94
4.1.3.3.3 DHCP (Dynamic Host Configuration Protocol)...........................95
4.1.3.3.4 DNS (Domain Name Systems).....................................................96
4.1.3.3.5 SNTP-Client (Simple Network Time Protocol)............................96
4.1.3.3.6 FTP-Server (File Transfer Protocol).............................................96
4.1.3.3.7 SMTP (Simple Mail Transfer Protocol) .......................................98
4.1.3.4 Anwendungsprotokolle.................................................................98
4.2 MODBUS-Funktionen ...........................................................................99
4.2.1 Allgemeines.......................................................................................99
4.2.2 Anwendung der MODBUS-Funktionen..........................................101
4.2.3 Beschreibung der MODBUS-Funktionen .......................................102
4.2.3.1 Funktionscode FC1 (Read Coils)................................................103
4.2.3.2 Funktionscode FC2 (Read Input Discretes)................................104
4.2.3.3 Funktionscode FC3 (Read multiple registers)............................105
4.2.3.4 Funktionscode FC4 (Read input registers) .................................105
4.2.3.5 Funktionscode FC5 (Write Coil) ................................................107
4.2.3.6 Funktionscode FC6 (Write single register).................................108
4.2.3.7 Funktionscode FC7 (Read Exception Status).............................109
4.2.3.8 Funktionscode FC11 (Get comm event counter)........................110
4.2.3.9 Funktionscode FC15 (Force Multiple Coils)..............................111
4.2.3.10 Funktionscode FC16 (Write multiple registers) .........................112
4.2.3.11 Funktionscode FC23 (Read/Write multiple registers)................113
4.2.4 MODBUS Register Mapping ..........................................................115
4.2.5 Interne Variablen.............................................................................116
4.2.5.1 Beschreibung der internen Variablen .........................................118
4.2.5.1.1 Watchdog (Verhalten bei Feldbusausfall) ..................................118
4.2.5.1.2 Watchdog-Register: ....................................................................118
4.2.5.2 Diagnose Funktionen..................................................................122
4.2.5.3 Konfigurations-Funktionen.........................................................122
4.2.5.4 Firmware-Information.................................................................124
4.2.5.5 Konstanten-Register....................................................................126
5 Busklemmen ............................................................................................128
5.1 Übersicht ..............................................................................................128
5.1.1 Digitale Eingangsklemmen..............................................................128
5.1.2 Digitale Ausgangsklemmen.............................................................130
5.1.3 Analoge Eingangsklemmen.............................................................131