Download NX-CIF Serial Communications Interface Units User`s Manual

7 Serial Communications
Step
Process
Communications master processing
Communications
CIF Unit processing
direction*1
2
Input
response
when
there is no
input data
• The communications master outputs
the following output notification data.
• The communications master has not
yet received input data, so the Input
SID Response remains at 00 hex.
Output SID
00 hex
Input SID
Response
Output Data
Type
Output Sub Info Output Data
Length
Output Data
4
Data
reception
Inputting
the first
data
→
---
The CIF Unit receives data from the serial
line.
• The CIF Unit inputs the following input
notification data.
• The communications master
receives the input notification data
given on the right.
• The CIF Unit sets the Input SID to 01 hex
to tell the communications master that the
first input data is included in the input notification data.
• The Input SID is 01 hex, so the master knows that the first input data is
included in the input notification data
that was received.
• The input data is stored in the
receive buffer.
First input
response
Port Status
Input SID
Output SID
Response
Input Data Type
Input Sub Info
Input Data Length
Input Data
01 hex
The first
data
received
from the
serial line
7
• The communications master outputs
the following output notification data.
• The CIF Unit receives the output notification data given on the left.
• The communications master sets the
Input SID Response to the value of
the Input SID (01 hex) to tell the CIF
Unit that the communications master
has normally received the first input
data.
• The CIF Unit knows that the communications master has normally received the
first input data because the Input SID
Response in the output notification data is
01 hex.
→
Output SID
01 hex
Input SID
Response
Output Data
Type
Output Sub Info Output Data
Length
Output Data
NX-series Communications Interface Units User’s Manual (W540)
7-7
7-3-2 SIDs and SID Responses
5
←
7-3 Data Used in PDO Communications
3
The CIF Unit receives the output notification
data given on the left.