YASKAWA GPD 315/V7, Техническое руководство

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GPD315 Modbus RTU Technical Manual TM 4325
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The data section of the response message contains 8 upper and 8 lower bits of data for each
register that is being written to.
A CRC-16 value is generated from a calculation using the values of the address, function code,
starting register number, quantity, number of data bytes, and data sections of the message. The
procedure for calculating a CRC-16 is described at the end of this chapter. When the slave
receives the command message it calculates a CRC-16 value and compares it to the one in
CRC-16 field of the command message. If these two CRC-16 values are the same the slave has
received the proper command message. If these two CRC-16 values are not the same the slave
does not respond.
If the command message has a valid slave address, function code, starting register number,
quantity, number of data bytes, and data values, the slave will respond with a normal response
message. If the command message has an invalid slave address, function code, starting register
number, quantity, number of data bytes, and/or data values the slave will respond with a fault
response message.
Write Registers Normal Response
Table 4-9 Write Registers Normal Response Message
Slave Address 01h
Function Code 10h
Upper 00h
Starting Register
Lower 01h
Upper 00h
Quantity
Lower 02h
Lower 10h
CRC-16
Upper 08h
The normal response message contains the same slave address and function code as the
command message, indicating to the master which slave is responding and to what type of
function it is responding.
The starting number is the first register that was written to. In the response message above the
starting number is 01h, indicating that the first register is the operation command.
The quantity indicates how many consecutive registers were written to.
A CRC-16 value is generated from a calculation using the values of the address, function code,
starting register number, and quantity value of the message. The procedure for calculating a
CRC-16 value is described at the end of this chapter. When the master receives the response
message it calculates a CRC-16 value and compares it to the one in the CRC-16 field of the
response message. If these two CRC-16 values are the same the master has received the
proper response message.