7 Serial Communications
7 - 14
NX-series Communications Interface Units User’s Manual (W540)
Step Process
CPU Unit or communications master
processing
Communi-
cations
direc
tion
*1
CIF Unit processing
1 Output-
ting
string
fro
m
A to
T
• The communications master outputs the
ou
tput notification data given below to
pass the following part of the text string to
the CIF Unit: ABCDEFGHIJKLM-
NOPQRST.
• The above output notification
data
is held
until the CIF Unit sends the input notifica-
tion data in which the Output SID
R
e
sponse is 01 hex.
The CIF Unit receives the outpu
t notifica-
tion data given on the left.
2 Output
response
fo
r A to T
• The communications master receives the
input notification data given on the right.
• The communications master knows that
ABCD
E
FGHIJKLMNOPQRST was nor-
mally received by the CIF Unit because
the
Output SID Response in the input
notification data is 01 hex.
The CIF Unit inputs the following input noti-
fication data to tell the CPU Unit or com-
munications master that
ABCDEFGHIJKLMNOPQRST wa
s
receiv
ed normally.
3 Sending
A to
T
--- The CIF Unit sends ABCDEFGHIJKLM-
NOPQRST to the serial line.
*2
4 Output-
ting
UVWXY
Z
The communications master outputs th
e
output notification data given below to pass
the following part of the text string to the
CIF Unit: UVWXYZ.
The CIF Unit receives the outpu
t notifica-
tion data given on the left.
20 bytes
01 hex
00 hex
1000 hex
0000 hex
0014 hex
41 hex,
42 hex,
:
53 hex,
54 hex
Incremented.
There is send
data that is not
the final.
A to T
Output SID
Input SID
Response
Output Data
Type
Output Sub Info
Output Data
Length
Output Data 01
to 05
There is data in
the send buffer.
Set the Output
SID.
0011 hex
00 hex
01 hex
0000 hex
0000 hex
0000 hex
00 hex,
00 hex,
00 hex,
00 hex
Input Data 01
Port Status
Input SID
Output SID
Response
Input Data Type
Input Sub Info
Input Data Length
02 hex
00 hex
2000 hex
0000 hex
0006 hex
55 hex,
56 hex,
57 hex,
58 hex,
59 hex,
5A hex,
00 hex,
:
Incremented.
This is the final
send data.
6 bytes
UVWXYZ
Output SID
Input SID
Response
Output Data
Type
Output Sub Info
Output Data
Length
Output Data 01
to 05