Communication Protocol
VD300 Series Inverter User Manual
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unsigned int crc_value=0xffff; while(data_length--)
{
crc_value^=*dat+;
for(i=0; i<8; i++)
{
if(crc_value&0x0001)
crc_value=(crc_value>>1)^0xa001;
else
crc_value=crc_value>>1;
}
}
return(crc_value);
}
In logic ladder, CKSM calculates CRC value according to frame content, adopting table look-up
method, this method is simple in program, quick calculating speed, but with big occupying ROM
space. Please consider carefully in application with requirement on program space.
9.6.4 Communication Data Address Definition
The part is address definition of communication data, used to control inverter operating, acquiring
inverter status message and inverter related function parameter setup etc.
①
The rules of parameter address of the function codes
Take sequence number of function code as parameter corresponding to register address, but need to
be transferred into hexadecimal. Such as P05.11, the hexadecimal communication address is 050BH,
P13.22 hexadecimal communication address is 0D16H.
Note: P30 group is manufacturer setting parameter, it cannot be read or changed. Some parameter
cannot be changed when inverter is in operation, but some parameter cannot be changed no matter if
inverter is run or not. When changing function code parameter, pay attention to the parameter setting
range, unit and related illustration.
Furthermore, since EEPROM is saved frequently, thus will it reducing lifetime. For user, some
function code under communication mode is not needed to be saved, only by changing the value of
RAM can meet application requirement. In order to realize the function, getting the corresponding
upper address of function code add with 80H(64 expressed in hexadecimal). For example, write
function code P11.02 is needed to be saved to EEPROM, then set the address as 0B02H, then only
change the RAM value and no need to be saved to EEPROM, by setting the address as 8B02H which
only used in writing RAM not used in read function, reading this address is Disabled.
②
Other function address description:
Function
Address
Definition
Date Description
R/W
Property
0.01H: Forward rotation
0.002H: Reverse rotation
0.003H: Stop
0.004H: Coast to stop
0.005H: Fault reset
Communication
control order
30000H
0.006H: Forward jog
R/W
Summary of Contents for VD300 Series
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