105BCommunication processor
12.3 Point-to-Point (PtP) communication
S7-1200 Programmable controller
System Manual, 11/2011, A5E02486680-05
545
Table 12- 24 Data types for the parameters
Parameter and type
Data type
Description
EN_R
IN
Bool
When this input is TRUE and a message is available, the message is
transferred from the CM or CB to the BUFFER. When EN_R is FALSE, the CM
or CB is checked for messages and NDR, ERROR and STATUS output are
updated, but the message is not transferred to the BUFFER. (Default value: 0)
PORT
IN
PORT
After you install and configure a CM or CB communication device, the port
identifier appears in the parameter helper drop-list available at the PORT box
connection. The assigned CM or CB port value is the device configuration
property "hardware identifier". The port symbolic name is assigned in the
"System constants" tab of the PLC tag table. (Default value: 0)
BUFFER
IN
Variant
This parameter points to the starting location of the receive buffer. This buffer
should be large enough to receive the maximum length message.
Boolean data or Boolean arrays are not supported. (Default value: 0)
NDR
OUT
Bool
TRUE for one execution when new data is ready and operation is complete
with no errors.
ERROR
OUT
Bool
TRUE for one execution after the operation was completed with an error.
STATUS
OUT
Word
Execution condition code (Default value: 0)
LENGTH
OUT
UInt
Length of the returned message in bytes (Default value: 0)
The STATUS value is valid when either NDR or ERROR is TRUE. The STATUS value
provides the reason for termination of the receive operation in the CM or CB. This is typically
a positive value, indicating that the receive operation was successful and that the receive
process terminated normally. If the STATUS value is negative (the Most Significant Bit of the
hexadecimal value is set), the receive operation was terminated for an error condition such
as parity, framing, or overrun errors.
Each PtP communication interface can buffer up to a maximum of 1024 bytes. This could be
one large message or several smaller messages. If more than one message is available in
the CM or CB, the RCV_PTP instruction returns the oldest message available. A subsequent
RCV_PTP instruction execution returns the next oldest message available.
Table 12- 25 Condition codes
STATUS (W#16#...) Description
0000
No buffer present
80E0
Message terminated because the receive buffer is full
80E1
Message terminated due to parity error
80E2
Message terminated due to framing error
80E3
Message terminated due to overrun error
80E4
Message terminated because calculated length exceeds buffer size
80E5
Reverse bias signal (wire break condition)
0094
Message terminated due to received maximum character length
0095
Message terminated because of message timeout
0096
Message terminated because of inter-character timeout
0097
Message terminated because of response timeout
0098
Message terminated because the "N+LEN+M" length condition was satisfied
