User`s manual

192
CHAPTER 5 CHANGING SEND AND RECEIVE
DATA LENGTH UNITS TO BYTE
UNITS (WORD/BYTES UNITS
SETTING)
The word units are used for the data length (count) of the amount of data sent/received using the following data
communication functions in data communication between the Q series C24 and the external device.
This chapter explains how to change the units (word to byte, byte to word) of the data length (count) sent/received with
the following data communication functions.
The data length units can be set for each Q series C24 interface. The Q series C24 controls the number of data to be
transmitted to the external unit and the number of data when it requests the programmable controller CPU to read the
data received from the external device according to the units set by the user.
(1) Data communication functions and buffer memory related to data length units
The following lists the data communications functions and buffer memory related to the data length units.
(The buffer memory addresses in the table are the default value.)
(2) How to change the units of the data length (count)
The units of the data length (count) can be changed using one of the following procedures.
• Changing via GX Configurator-SC: The units can be changed on the GX Configurator-SC's system setting
screen.
• Changing via the programmable controller CPU: The units can be changed with the CSET instruction.
Change the units of the data length (count) according to the explanation in Page 384, Section 17.4 of this
manual.
Data communications function
Name of buffer memory related to data length units
(Address CH1, CH2)
Reference manual
MC protocol On-demand function On-demand data length designation area (A1H, 141H)
( MELSEC Communication
Protocol Reference Manual)
Nonprocedural
protocol
Data transmit
function
Send data count storage area (400H, 800H)
 User's manual (Basic)
Data receive function
Received data count designation area (A4H, 144H)
Receive data count storage area (600H, A00H)
Bidirectional
protocol
Data transmit
function
Send data count storage area (400H, 800H)
 User's manual (Basic)
Data receive function Receive data count storage area (600H, A00H)