9.
COMMUNICATIONS
IN
THE NOIPROTOCOL MODE
MELSEC-A
9.3
Programming Hlntr
9.3.1
To
write
data
to
tho
speck1
use
area
In
bulhr
memory
Buffer memory is not backed up by a battery.
When the power is turned
ON,
the
PC
CPU is reset, or the mode is
switched, all data in the buffer is set to default value.
Therefore, whenever the power is turned
ON,
the CPU is reset, or the
mode is switched, any data which has been changed from a default
value must be written to the buffer.
Except for the mode switching area, data can only
be
written to the
special applications area (1 OOH to
11
FH) using the TO instruction in a
sequence program.
If
data is written to the buffer memory using the
command in a computer program, the AJ71C24
will
not operate correctly.
Never
try
to write data using a computer program.
If
the
following functions are used in combination with the dedicated
protocol, make sure to allocate
the
user area
in
buffer memory
so
that
the same area
will
not be used by different functions.
If
the same area is allocated to different functions, the data in this area
is rewritten and communications
will
not be correctly executed.
0
No-protocol mode transmission or bidirectional mode transmission
0
No-protocol mode receive or bidirectional mode receive
0
Buffer memory read/write (CR/CW command) function
0
On-demand function
The memory areas preceding and following the special use area cannot
be allocated as
a
single area. The areas
OH
to FFH and 120H
to
7FFH
must be recognized as independent areas.
If
the designation is made to process the sendheceive data in the
no-protocol mode or bidirectional mode in units of words or bytes, the
on-demand data is processed in the same designated unit.
9-3
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com
To Next Page
Loading...
