NRT405F901 manual
Chapter 16
Modbus signal types
35
Tx+ -----|---------------------------------------- A (or B)
|
Rx+ -----|
Tx- -----|---------------------------------------- B (or A)
|
Rx- -----|
Bit rate, two stop bits, parity is next layer.
These settings must correspond to the settings in the main unit. Find out what the settings for
the main unit are, and then enter the same settings into the controller.
Parity can be set to odd, even (FS) or none. If no parity is set, two stop bits will
automatically be used. If odd or even parity is set only one stop bit will be used, or the total
amount of bits will be too great. 1 start bit, 8 data bits, 1 parity bit and 1 stop bit gives a total
of 11 bits, which is the maximum.