Enter Command - YASKAWA GA700 Technical Manual

5.3 MEMOBUS/Modbus Communications
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Loopback Test
The loopback test is performed using the function code 08 (Hex.). The loopback test returns the command
message as a response message. The test is used to check communication between the master and slave. The test
code and data can use desired values.
The following table shows examples of messages given out when the loopback test is performed with the drive of
slave 1.
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Writing to Multiple Holding Registers
The respective data that was set can be written to a set number of holding registers from the number that is set
using the function code 10 (Hex.). The write data requires that the number of the holding registers and each 8
higher bits and 8 lower bits be configured in order inside the command message. The number of writable holding
registers is 16.
The following table shows example messages when Forward run is set in the drive of slave 1 from the PLC with
60.00 Hz frequency reference.
When the parameter value is rewritten using the write command via the H5-11 [Communications ENTER Func
Select] setting, the Enter command is required to save and enable the contents of the changes. For details, refer to
"H5-11 [Communications ENTER Func Select]" and "Enter command."
Note:
The number of bytes set within the command message determines the data quantity × 2 during the command message. The response
message will also be handled the same way.
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Enter Command

When writing the parameters from the PLC to the drive using MEMOBUS/Modbus communications, enabling
these parameters from the Enter command will depend on the H5-11 [Communications ENTER Func Select]
setting. This section explains the Enter command.
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Types of Enter Command
The drive supports the two Enter commands shown on the following list.
The Enter command executes by writing 0 to register No. 0900 or 0910 (Hex.). These registers can only be
written. If data is read using these registers, an error is generated.
238 YASKAWA ELECTRIC SIEP C710617 01B YASKAWA AC Drive GA700 Technical Manual