Computer Hardware User Manual

438
The transmission message and reception message have the following struc-
ture.
Header Address Length Data Error check Terminator
Item Function
Header Set the data that indicates the beginning of the message.
Address Set the node number or other identifier that indicates the
destination for the message.
Length The data length (number of bytes) is added automatically.
Data Set the message contents.
Error check code Set SUM, LRC, or CRC as the error check code. The specified
error check code will be added automatically when transmitting.
When receiving, error control will be performed automatically
based on the error check code specified in the message and
the specified amount (length) of data will be received.
Terminator Set the data that indicates the end of the message.
The following attributes can be set for each item in the transmission or reception
message. The abbreviation “R M” stands for reception message and “T M”
stands for transmission message.
Data attribute
Header Address Length Data Error check Terminator
T M R M T M R M T M R M T M R M T M R M T M R M
Constant
ASCII
“”
HEX
[]
Yes Yes Yes Yes --- --- Yes Yes --- --- Yes Yes
Special characters
CR, STX, etc.
Yes Yes --- --- --- --- Yes Yes --- --- Yes Yes
No variable
conversion
First-order equation
using variable (N)
--- --- Yes Yes --- --- Yes Yes --- --- --- ---
Wild card () --- --- --- Yes --- --- --- Yes --- --- --- ---
Read word (R) --- --- Yes Yes --- --- Yes Yes --- --- --- ---
Write word (W) --- --- --- Yes --- --- --- Yes --- --- --- ---
Automatic variable:
LNG
--- --- --- --- Yes Yes --- --- --- --- --- ---
Automatic variable:
SUM, LRC, and CRC
--- --- --- --- --- --- --- --- Yes Yes --- ---
Variable
ASC
First-order equation
using variable (N)
--- --- Yes Yes --- --- Yes Yes --- --- --- ---
conversion
Wild card () --- --- --- Yes --- --- --- Yes --- --- --- ---
Read word (R) --- --- Yes Yes --- --- Yes Yes --- --- --- ---
Write word (W) --- --- --- Yes --- --- --- Yes --- --- --- ---
Automatic variable:
LNG
--- --- --- --- Yes --- --- --- --- --- --- ---
Automatic variable:
SUM, LRC, and CRC
--- --- --- --- --- --- --- --- Yes --- --- ---
Variable
HEX
First-order equation
using variable (N)
--- --- Yes Yes --- --- Yes Yes --- --- --- ---
conversion
Wild card () --- --- --- Yes --- --- --- Yes --- --- --- ---
Read word (R) --- --- Yes Yes --- --- Yes Yes --- --- --- ---
Write word (W) --- --- --- Yes --- --- --- Yes --- --- --- ---
Automatic variable:
LNG
--- --- --- --- --- Yes --- --- --- --- --- ---
Automatic variable:
SUM, LRC, and CRC
--- --- --- --- --- --- --- --- --- Yes --- ---
Transmission/Reception
Message Structure
The Protocol Macro Function
Section 8-6