Yokogawa JUXTA M Series Digital Limit Alarms MVTK - Manual (Page 42)

4-2
<Toc> <Ind> <4. Ladder Communication >
IM 77J04J11-01E 1st Edition : 2006.08.25-00
4.2 Commands/Responses at the PLC
The PLC sends commands and receives responses to these commands. The com-
mands and responses that can be used are as follows.
4.2.1 Configuration of Command/Response
Commands sent from the PLC to the M Series and responses from the M Series with
respect to a command sent from the PLC consist of the following elements.
Number of Bytes 1 1 2 2 1 1 1 1
Number of BCD Digits 2 2 1 4 4 2 2 1 1 1
Command/Response
element
Address
number
(ADR)
Parameter
number
CPU
number
01
CR
(0D)
LF
(0A)
0 R/W +/- 0 Data
Can be changed only during a read operation.
A maximum of 64 data items
(1) (2) (3) (4) (5) (7) (8) (9) (6)
(1) Address Number (01 to 99)
Address numbers are used by the PLC to identify the M Series at the communication
destination. (Identification numbers specific to individual M Series.)
(2) CPU Number
This is fixed to 01.
(3) Parameter Number
This is 4-digit BCD data of a D register number with its leading character D removed.
I relays cannot be specified.
See Also
Chapter 6 for more information on D registers.
(4) 0
This is fixed to 0.
(5) 0
This is fixed to 0.
(6) R/W
0: Read
1: Write
(7) +/-
0: Positive data (+)
1: Negative data (-)
(8) Data
For read operation, this is the number of data items to be read.
For write operation, it is the setting data.
(9) CR and LF
These control codes indicate the end of a command. The corresponding control
character strings for CR and LF are 0D and 0A in hexadecimal in ASCII code, respec-
tively.