User manual

Chapter Two Operation
MAN_905G_1.16 Page 22
voltage is also monitored, and an alarm is available at register 4309. This becomes active if
the supply voltage falls below 8.0V, and clears when the supply voltage rises above 9.0V.
I/O Register Description I/O Register Description
4300 Input value DIO 1 4320 Output value DIO 1
4301 Input value DIO 2 4321 Output value DIO 2
4302 Input value DIO 3 4322 Output value DIO 3
4303 Input value DIO 4 4323 Output value DIO 4
4304 Input value DIO 5 4324 Output value DIO 5
4305 Input value DIO 6 4325 Output value DIO 6
4306 Input value DIO 7 4326 Output value DIO 7
4307 Input value DIO 8 4327 Output value DIO 8
4308 Low battery voltage status
4309 Supply voltage fail status
4310 Battery voltage value
4311 Supply voltage value
2.4 The Host - 905G Link
For the host device, the 905G "looks" like a single device (or a "virtual PLC"), containing the
I/O for the complete wireless I/O system.
DATABASE
I/O
"VIRTUAL PLC"
DATA-BUS
“HOST DEVICE”
905U-G
2.4.1 Modbus / DF1
The user selects whether the 905U-G-MD1 should act as a Modbus Master or Modbus Slave
or DF1 device.
The data type and baud rate of the serial communications must be configured at the 905G to
match the host. Data types can be 7 or 8 bit, even/odd/no parity, with 1 or 2 stop bits. Data
rates can be 300 - 19200 baud.
The full 905G database (4300 registers) can be accessed by the Host Device.