Direct Connection Function; Nt Link - Omron NT11 - 01-2004 User Manual

Direct Connection Function

1-5

Direct Connection Function

Features of the Direct Connection Function
1-5-1

NT Link

Features of the NT Link
The communication method applied between the NT11 and the PLC is either
a host link or NT link.
The NT11 can be used to refer to the contents necessary for the display infor-
mation or to allocate the bits and words used for storing the input data to any
area in the PLC. The NT11 can directly write and read such allocated bits and
words so as to change the display elements, control the operating status, and
notify the status.
This function is called the "direct connection function". The NT11 is designed
exclusively for use with the direct connection.
The bits and words allocated by the direct connection function are called "allo-
cated bit" and "allocated word" respectively.
This function allows to read the information to be displayed on the NT11 from
the memory area in the PLC and to write it to the memory table in the NT11.
Also, the data input on the NT11 can be written to the PLC's memory area.
The NT11 screen status can be switched according to the PLC's memory
area, and the NT11's status data can be written to the PLC's memory area.
NT11
• The bits and words referring to operating status and work instruction infor-
mation and those for storing input data can be freely allocated to almost
any part of the PLC memory. Bits and words in the PLC can be refer-
enced from any memory table.
• The NT11 can directly refer to PLC bit and word data so that it can be
connected to a PLC without changing the PLC program which controls
currently running production line.
• The area to control and notify the NT11 status, including display screens,
ON/OFF of the backlight, and printing of daily reports and display histo-
ries, can be freely allocated to any part of the PLC memory.
The direct connection function allows the NT11 to directly read and write
almost all bits and words in the PLC and to automatically change the NT11
screen display. This function can reduce the load on the PLC so that the pro-
gram development efficiency of the PLC improves.
The NT link is a new communication method applied between the NT11 and a
PLC.
The NT link uses the direct connection function and can execute high speed
communications with a CPU (built-in NT link) of the CQM1, C200HS, and
other PLCs.
• High speed communications with specific types of PLCs can be executed.
• Writing in units of bits to the PLC memory area is possible. (*)
PLC
Data memory area Internal relay area
Auxiliary relay area
Timer/counter
Section 1-5
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