2.4.2 Communicating with Unsupported Device/PLC (Memory
Link)
To communicate with a device –
such as a PC or microcomputer board (hereafter called the "host") –
that does not have its own communication protocol, the host will
send write or read requests to the display unit. The display unit
displays or otherwise operates on the data sent by the host's write
request. In response to read requests, the display unit returns
stored data to the host.
This communication method that is realized by running the program
on the host side is called "Memory Link".
Setup Process
To use the host as a device/PLC unit, configure the [Device/PLC]
settings as follows.
Usable
Addresses
For the display unit to get the necessary display data from the
host, set an address to reference the data and use it in a Part or
script. There are two types of addresses you can reference on the
display unit.
The System Area is used as the medium for
read and write requests to and from the host. The System Area is
the Memory Link Method's communication area.
 A.1.2
System Area (Memory Link Area)
For example, to set a Word Switch address,
select [#MEMLINK] from [Device/PLC] and enter the address (for
example, "100").
For example, an Input Address screen on a Word Switch.
When using Memory Link communication with the
display unit internal device [#INTERNAL], you can only use the
[USR] area. For example, you can use the internal device as a
temporary storage area when you need to refer to calculated
values.
You may use all areas as you like, up to 30,000 Words. The text
data storage order is fixed to L/H, no matter what the [Text Data
Mode] property is set to in the System Settings window's
[Device/PLC] page.
You cannot use the internal device with Memory Link
communication.
From [Device/PLC], select [#INTERNAL] and
enter an address (for example, "USR0100".
For example, an Input Address screen on a Word Switch.
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