Fuji Electric FRENIC-AQUA series User Manual page 44

Character format
Each byte of a message is transmitted as a character. Character formats are described on the
following page.
A character comprises a start bit (logical value 0), 8-bit data, an additional (optional) parity bit,
and a stop bit (logical value 1).
A character always consists of eleven bits, and the number of stop bits varies depending on
whether parity exists.
Without parity
LSB
0 1 2
Start Data
With parity
LSB
0 1 2
Start Data
- Modbus RTU protocol has the above character format as specified by the rule. But,
some devices use the format "No parity + 1 stop bit." For connection with these
devices, the inverter supports the parity bit selection (y06=3, y16=3). When y06=3 or
y16=3, the protocol is given the following character format.
LSB
0 1 2
Start Data
3 4 5 6 7
3 4 5 6 7
3 4 5 6 7
3-3
3.1 Messages
8 9 10
Stop
8 9
Parity (optional)
MSB
8 9
Stop
MSB
MSB
10
Stop