D–5
D–5
Using the D2–DCM with Modems
Data Communications Module, 2nd Edition, 2/03
A couple of scenarios have been mentioned where you may be using a D2–DCM connected
to a modem as the master station and a DL240 CPU connected to a modem as the slave
station. If you have such a situation, there are a couple of things that you may have to take into
consideration.
If you are using a radio modem connected to
the bottom port of a DL240, you will probably
have to set a delay time for the CPU port. You
can do this by loading a BCD value into
V7632. This is a special V-memory location
which defines the baud rate and/or time delay
for the bottom port. It is recommended that
you do this on the first scan within your ladder
program. The following diagram provides a
table of the settings and an example of some
simple setup logic that could be included in
your RLL program.
Delay Codes
00 No delay
01 2ms delay
02 5ms delay
03 10ms delay
04 20ms delay
05 50ms delay
06 100ms delay
07 500ms delay
Baud Rate Codes
00: 300 baud
01: 1200 baud
02: 9600 baud
03: 19200 baud
V7632
MSB
LSB
X
X
X
X
SP0
LD
K203
Use the LD (Load) instruction to load the BCD codes for
each parameter into the accumlator. The number 0203 is
just the code used for our particular example, which is a
5ms delay, 19.2K baud.
OUT
V7632
Place the value in memory location V7632
Example:
First Scan Only, Load Delay Time of 5ms & Baud Rate of 19200 for Bottom Port
XX
KKVV
X
After the parameter setup rung(s) above, we begin the
normal ladder program. Use your actual program for this
and the following rungs.
X
Y
Main Ladder Program Begins
Setup Rung
Delay Time
Baud Rate
Delay Codes
00 No delay
01 2ms delay
02 5ms delay
03 10ms delay
04 20ms delay
05 50ms delay
06 100ms delay
07 500ms delay
Baud Rate Codes
00: 300 baud
01: 1200 baud
02: 9600 baud
03: 19200 baud
V7632
0
1
2
3
4
5
6
7
8
Bit
1
0
0
0
1
0
0
0
0
0
0
0 0 1 0
0
2
3
0
0
9
10
11
12
13
14
15
Delay Time
Considerations for
Networks with DL240
Slaves
Содержание D2-DCM
Страница 4: ...D2 DCM Data Communications Module Manual Number D2 DCM M...
Страница 37: ...1A Cable Diagrams...
Страница 47: ...Data Communications Module 2nd Edition 2 03 B RLL Communications Programs...
Страница 58: ...Data Communications Module 2nd Edition 2 03 C Using the D2 DCM with MODBUS...
Страница 67: ...Data Communications Module 2nd Edition 2 03 D Using the D2 DCM with Modems...
