User`s guide

195
CHAPTER 8 - CFW-08 OPTIONS AND ACCESSORIES
Bit Number
Bit 100
Bit 101
Bit 102
Bit 103
Bit 104
Bit 105
Bit 106
Bit 107
Command Bits
Function
0 = Ramp disable (stops)
1 = Ramp enable (runs)
0 = General disable
1 = General enable
0 = Counter-clockwise direction of rotation
1 = Clockwise direction of rotation
0 = JOG disable
1 = JOG enable
0 = Goes to local mode
1 = Goes to remote mode
Not used
Not used
0 = It does not reset inverter
1 = It resets inverter
8.25.3
Detailed Function
Description
This section describes in details the functions that are
available in the CFW-08 fortheModbus RTU communication.
Please note the following during the message preparation:
Values are always transmitted as hexadecimal values.
The address of one data, the data number and the value of
the registers are always represented through 16 bits.Thus
these fields are transmitted by using two bytes (high and
low). To access the bits, and the form to represent one bit
depend on the used function.
The messages, both for enquiry and response, cannot be
longer than 128 bytes.
The maximum number of read or written parameters in a
single telegram cannot be bigger than 8.
The resolution of each parameter or basic variable is as
described in item 8.24.3.2.
8.25.3.1
Function 01 -
Read Coils
It reads the content of an internal group of bits that must
compulsorily in a numerical sequence. This function has the
following structure for the read and response messages (the
valuesarealways hexadecimal, andeach fieldrepresents one
byte):
Query (Master)
Slaveaddress
Function
Initial bit address (byte high)
Initial bit address (byte low)
Number of bits (byte high)
Number of bits (byte low)
CRC-
CRC+
Response (Slave)
Slaveaddress
Function
Byte Count Field (number of data bytes)
Byte 1
Byte 2
Byte 3
etc
CRC-
CRC+
Table 8.16
- Command bits signified
Table 8.17
- Function 01 structure
The command bits are available to read and write and they
have the same functionof thelogic commandbits0 to 7 (basic
variable 3), however no requiring the use of the mask. The
basic variable 3 write influences the status of these bits.