Control Techniques COMMANDER SE, Руководство для продвинутых пользователей

Страница: 14 / 195

14
Commander SE Advanced User Guide
Issue Number: 4
decimal, so this is the final BCC value. 53 decimal is the ASCII character '5'.
The drive should reply with ACK control character if the message was received correctly, and the BCC agrees with the drive
calculation.
1.3.3 Re-writing data
Once a complete 'write' message has been sent to a drive, and the drive has responded with either a 'ACK' or 'NAK'
character, subsequent 'write' messages to that particular drive can use a re-write message structure. The address does not
need to be re-transmitted. The 're-write' message structure is as follows:
When a different drive needs to be addressed, or an ACK or NAK response is not received from the current drive addressed,
the 're-write' facility can no longer be used. The particular drive can only be addressed by using the full 'write' message with
the correct address, etc.
1.4 Modbus RTU
1.4.1 Parameters
11.24 Serial Communication Mode
0 AnSI Ansi protocol half duplex serial communications 2 wire
1 rtu Modbus RTU high data rate protocol
2 F.bus Fieldbus communications mode
To implement Modbus RTU, parameter 11.24 should be set to 1
11.25 Data (baud) rate
0 2.4 2,400 bits/sec
1 4.8 4,800 bits/sec
2 9.6 9,600 bits/sec
3 19.2 19,200 bits/sec
Used to select the communications port data (baud) rate.
11.23 Modbus node address
Used to define the network node address for the Commander SE. All nodes on a Modbus network MUST be configured with
a unique node address.
1.4.2 Modbus frame specification
The COMMANDER SE does not use the parity bit.
1.4.3 Modbus register value
All Commander SE parameters are mapped to the 4XXXX series of Modbus registers. To convert from a parameter number
to a Modbus register, remove the decimal point from the parameter number e.g. parameter 11.22 = register 41122. All
parameters (including bit parameters) are handled as signed 16 bit values.
1.4.4 Supported functions
0x03 (3) Read holding registers Read Multiple Parameters
0x10 (16) Preset multiple registers Write Multiple Parameters
0x17 (23) Read/Write registers Read and Write Multiple Parameters
When using multiple write or read commands, the parameters written to or read from must be consecutive. If a block of
parameters is written to or read from where there is a missing parameter, the slave will respond with an exception code.
Therefore this block should be split into a number of smaller blocks so as not to write to or read from a missing parameter.
The maximum number of consecutive parameters that can be written to or read from is 16.
1.4.5 Broadcast messages
Commander SE also supports broadcast messages. If the master controller sends a WRITE message to node address 0, all
nodes will accept the message but none will reply to the master.
CC Parameter Data CC BCC
STX M1 M2 P1 P2 D1 D2 .... Dn ETX BCC
Range Default Type Limitations Level 2 parameter
0 ~ 2 0 (AnSi) RW P 41
Range Default Type Limitations Level 2 parameter
0 ~ 3 1 (4.8) RW P 42
Range Default Type Limitations Level 2 parameter
0.1 ~ 24.7 1.1 RW P 43
1 start bit 8 data bits 1 stop bit