DIA1
First 3 digits of 1st row display the unit id.
4th digit displays the status as given below.
r - Receiving the data.
t - Transmitting the data.
u - Wrong unit id.
o - Any one of the following error (parity, over run or framing error)
F – Wrong function which MODBUS does not supports.
A – Wrong address.
2nd row displays the baud rate of the communication.
3rd row displays parity and nos. of stop bits.
DIA2
It gives information on the model no and the version number.