Configuring and Parameter Assignment the CP 440 
  5.4 Configuration data 
Point-to-point connection CP 440 Installation and Parameter Assignment 
Manual, 09/2007, A5E00057742-03 
79 
Receive Buffer on CP 
The following table describes the parameters for the CP receive buffer. 
Table 5-13  Receive buffer on CP (3964(R) procedure) 
Parameters  Description  Value Range  Default Value 
Delete CP receive 
buffer at startup 
During power up or during transition of the CPU from 
STOP to RUN the CP receive buffer is deleted. 
•  Yes 
•  No 
No 
Buffered receive 
message frames 
You can specify the number of receive message 
frames to be buffered in the CP receive buffer or to 
use the whole buffer. If you use the whole buffer of 
2000 bytes, the number of buffered receive message 
frames depends only on the length of the frames. 
If you specify "1" here and deactivate the following 
parameter "prevent overwrite" and cyclically read the 
received data from the user program, a current 
message frame will always be sent to the CPU. 
•  1 to 10 
•  Use whole buffer 
Use whole 
buffer 
Prevent overwrite  You can use this parameter to prevent data in the 
receive buffer being overwritten when the buffer is full. 
•  Yes 
•  No 
Yes 
 
Initial state of receive line 
The table below contains a description of the initial state of the receive line for the X27 
(RS 422) interface. RS 485 operation is not possible in conjunction with the 3964(R) 
procedure. 
Table 5-14  X27 (RS 422) Interface (3964(R) procedure) 
Parameters  Description  Value Range  Default Value 
none: This setting only makes sense with bus-
capable drivers. 
none 
R(A) 5V/R(B) 0V: Break detection is possible 
with this initial state. 
R(A) 5V / R(B) 0V 
(break detection) 
Initial state of 
receive line 
R(A) 0V/R(B) 5V: Break detection is not possible 
with this initial state. 
R(A) 0V / R(B) 5V 
R(A) 5V / R(B) 0V 
 
该文档是极速PDF编辑器生成,
如果想去掉该提示,请访问并下载:
http://www.jisupdfeditor.com/