Siemens SIMATIC S7-1200 - Page 1111

Communication processor and Modbus TCP
13.3 Point-to-point (PtP) communication
S7-1200 Programmable controller
System Manual, V4.2, 09/2016, A5E02486680-AK
1111
Parameter and type
Data type
Description
DATABITS IN UInt Bits per character (Default value: 1):
1 = 8 data bits, 2 = 7 data bits
STOPBITS IN UInt Stop bits (Default value: 1):
1 = 1 stop bit, 2 = 2 stop bits
FLOWCTRL* IN UInt Flow control (Default value: 1):
1 = No flow control, 2 = XON/XOFF, 3 = Hardware RTS always ON,
4 = Hardware RTS switched
XONCHAR
1
IN Char Specifies the character that is used as the XON character. This is typically a
DC1 character (16#11). This parameter is only evaluated if flow control is
enabled. (Default value: 16#11)
XOFFCHAR
1
IN Char Specifies the character that is used as the XOFF character. This is typically
a DC3 character (16#13). This parameter is only evaluated if flow control is
enabled. (Default value: 16#13)
WAITTIME
1
IN UInt Specifies how long to wait for a XON character after receiving a XOFF char-
acter, or how long to wait for the CTS signal after enabling RTS (0 to 65535
ms). This parameter is only evaluated if flow control is enabled. (Default
value: 2000)
MODE
2
IN UInt Specifies the selection of the module’s operating mode.
• 0 = Full duplex (RS232)
• 1 = Full duplex (RS422) four-wire mode (point-to-point), transmitter al-
ways enabled
• 2 = Full duplex (RS422) four-wire mode (multipoint master), transmitter
always enabled
• 3 = Full duplex (RS422) four-wire modemultipoint slave, transmitter
enabled while sending
• 4 = Half dubplex (RS485) two-wire mode
LINE_PRE IN UInt Specifies the inactive (idle) line condition. For RS422 and RS485 modules
the idle line condition is established by applying a bias voltage to the R(A)
and R(B) signals. The following selections are possible:
• 0 = Not biased (No Presetting) (default)
• 1 = Biased with R(A) > R(B) ≥ 0V; RS422 only
• 2 = Biased with R(B) > R(A) ≥ 0V; RS422 and RS485
BRK_DET IN UInt Enables/disables communications cable break detection. Enabling cable
break detection causes the module to indicate a fault when the communica-
tions cable is not connected to the module.
In RS422 Point-to-Point mode cable break detection is only possible when
Receive Line Presetting is used with bias applied so that R(A) > R(B) ≥ 0V.
• 0 -= No Cable Break Detection (default)
• 1 = Cable Break Detection enabled
DONE
OUT
Bool
TRUE for one execution after the last request was completed with no error
ERROR
OUT
Bool
TRUE for one execution after the last request was completed with an error
STATUS
OUT
Word
Execution condition code (Default value: 0)
1
Not applicable when Protocol=1 (3964(R) protocol)
2
Only modes 0 and 1 are valid when Protocol=1 (3964(R) protocol) depending on whether your CM module is an RS232
module or RS422 module.