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MELSEC-Q
11 INSTRUCTIONS AND FUNCTIONS
• Specify the maximum message length that can be transmitted to the message port in
<message length>. The specification range is from 1 to 256 bytes.
The necessary number of bytes can be found from the following. Note that if several
<output element> are specified in the ZMESSAGE PUT instruction, the necessary number
of bytes is the total value of all of <output element>.
Integer data
Single-precision floating point data
Double-precision floating point data
Character data
• • • •
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2 bytes per data
4 bytes per data
8 bytes per data
1 byte per character
(2 bytes per full-byte character)
Normally it is recommended to specify 256 bytes.
• Message ports should only be defined in one of the programs executed at any one
time in multitask operations by the ZMESSAGE instruction.
• In order to use the message ports, it is necessary to open the message ports by the
ZMESSAGE OPEN instruction after defining them by the ZMESSAGE instruction.
