Ucmm Tag Communications Communication Example; System Configuration; Communication Description - Mitsubishi Electric MELSEC iQ-R Series User Manual

13.4
UCMM Tag Communications Communication
Example
This section describes examples of executing UCMM tag communications between CC-Link IE TSN Plus modules.

System configuration

The following system configuration is used to explain communication examples of UCMM tag communications.
(1)
(1) Programmable controller system (originator)
• Power supply module: R61P
• CPU module: R04CPU
• CC-Link IE TSN Plus module: RJ71GN11-EIP (start I/O number: 0000H to 001FH, IP address: 192.168.1.5)
(2) Programmable controller system (target)
• Power supply module: R61P
• CPU module: R04CPU
• CC-Link IE TSN Plus module: RJ71GN11-EIP (start I/O number: 0000H to 001FH, IP address: 192.168.1.6)

Communication description

When the communication example for UCMM tag communications is executed, the following operation is performed.
Originator-side operation
■Write request to tags
By executing a UCMM tag communication write request, the device area data stored in D1000 or later is written to the Tag001
tag on the target side according to the requested size.
*1 If the requested data type is INT, request data consisting of the request data size  1 word (10 words in the program example) is sent.
If the requested data type is DINT, request data consisting of the request data size  2 words is sent.
■Tag read request
By executing a UCMM tag communication read request, the data set to the Tag002 tag on the target side is read according to
the requested size. From the read data, the amount according to the read data size (size stored in D3204) is stored in D2000
or later.
(Regardless of the tag data type of the external device, the received read data size is stored in units of words.)
In addition, the size of the data read from the tag of the external device depends on the read request data size set in the
output argument (i_uDataSize) of the module function block, as well as the external device tag data type (value stored in
*1*2
D3203).
*1 If the external device tag data type is INT, the read request data size  1 word is read.
If the external device tag data type is DINT, the read request data size  2 words is read.
*2 The read request tag data type set in the module function block input argument (i_uDataType) is used to perform a parameter check
when sending a request.
If the data type of the external device tag that was read is different, check whether the requested tag name and data size are correct.
Target-side operation
The current values of the tag data set in Tag001 and Tag002 are read and the current values are updated.
During target-side operation, both read and write requests from the originator side for the tag can be accepted.
However, if the data is updated due to a write request while the current value is being read, or if the data having its current
value updated is read due to a read request, it may result in a data inconsistency.
(2)
*1

13.4 UCMM Tag Communications Communication Example

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