Siemens SIMATIC S7 System Manual page 222

Program instructions
7.3 Communication
Table 7- 10
Byte
offset
A/P: Active/Passive selection (1 = Active, 0 = Passive)
1
Connection Type: The Connection Type informs the TCON instruction of the desired type of con-
2
nection: ISO-on-TCP = 12
Remote IP address: This is the IP address of the remote device in the case of an active connec-
3
tion. The IP address must be different than that of the local CPU and cannot be a multicast or
broadcast address. Since the S7-200 SMART supports routing, the IP address may be on a differ-
ent subnet than the local CPU.
If you set the IP address for a passive (server) connection, then the CPU only accepts a connec-
tion from the specified IP address. If you set the IP address to 0.0.0.0 for a passive connection, the
CPU accepts a connection from any IP address.
Remote TSAP: This is the Transport Service Access Point (TSAP) of the remote device. You use
4
the remote TSAP for ISO-on-TCP connections only. The remote TSAP is a string of 2 to 16 ASCII
characters.
Local TSAP: This is the Transport Service Access Point (TSAP) for the connection in local CPU.
5
You only use the local TSAP for ISO-on-TCP connections. The local TSAP is a string of 2 to 16
ASCII characters. If you use two characters, the TSAP must start with a hex "E0" character ($E0),
followed by another hex character (for example, "$E0$01"). You cannot use the string "SIMATIC-".
222
Definition of TCON instruction TABLE parameter structure for ISO-on-TCP
Bit 7 Bit 6
0 D A
1 A/P
1
2
3
4
5
6
7
8
9
to
25
26
to
42
Bit 5 Bit 4 Bit 3
E
Connection ID
(2 bytes)
Connection Type
Remote
IP
Address
3
Remote TSAP
String of 2 to 16 characters (3 to 17 bytes)
Local TSAP
String of 2 to 16 characters (3 to 17 bytes)
System Manual, V2.3, 07/2017, A5E03822230-AF
Bit 2 Bit 1
Error code (5 bits)
2
4
5
Bit 0
REQ
S7-200 SMART