Point-To-Point (Ptp) Communication - Siemens SIMATIC S7 System Manual

Table 12- 2 Termination and bias for the CB 1241
Terminating device (bias ON)
①
Connect M to the cable shield
②
A = TxD/RxD - (Green wire / Pin 8)
③
B = TxD/RxD + (Red wire / Pin 3)
12.3

Point-to-Point (PtP) communication

The CPU supports the following Point-to-Point communication (PtP) for character-based
serial protocols. PtP provides maximum freedom and flexibility, but requires extensive
implementation in the user program.
● PtP (Page 531)
● USS (Page 567)
● Modbus (Page 581)
PtP communication is serial communication that uses standard UARTs to support a variety
of baud rates and parity options. The RS232 and RS485 communication modules and the
RS485 communication board provide the electrical interfaces for performing the PtP
communications.
S7-1200 Programmable controller
System Manual, 11/2011, A5E02486680-05
12.3 Point-to-Point (PtP) communication
Non-terminating device (bias OFF)
PtP enables a wide variety of possibilities:
 The ability to send information directly to an external
device such as a printer
 The ability to receive information from other devices
such as barcode readers, RFID readers, third-party
camera or vision systems, and many other types of
devices
 The ability to exchange information, sending and
receiving data, with other devices such as GPS
devices, third-party camera or vision systems, radio
modems, and many more
105BCommunication processor
531