Goodrive100 inverters
Communication protocol
IKR Aandrijven en Besturen
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7.3 RTU mode
7.2.2.1 RTU communication frame format
If the controller is set to communicate by RTU mode in Modbus network every 8bit byte in the message
includes two 4Bit hex characters. Compared with ACSII mode, this mode can send more data at the same
baud rate.
Code system
·
1 start bit
·
7 or 8 digital bit, the minimum valid bit can be sent firstly. Every 8 bit frame includes two hex characters
(0...9, A...F)
·
1 even/odd check bit . If there is no checkout, the even/odd check bit is inexistent.
·
1 end bit (with checkout), 2 Bit(no checkout)
Error detection field
·
CRC
The data format is illustrated as below:
11-bit character frame (BIT1~BIT8 are the digital bits)
Start bit
BIT1
BIT2
BIT3
BIT4
BIT5
BIT6
BIT7
BIT8
Check
bit
End bit
10-bit character frame (BIT1~BIT7 are the digital bits)
Start bit
BIT1
BIT2
BIT3
BIT4
BIT5
BIT6
BIT7
Check
bit
End bit
In one character frame, the digital bit takes effect. The start bit, check bit and end bit is used to send the
