Hello Guys.
I like to know if any one knows abt this chip in details.
This chip is used to convert 2 input pulses to RS485 Modbus. PCB has a MAX487

My issue is figure out the Address, parity, stop and Data type. I am trying to connect this to an HMI.
Any help will be highly appreciated.

Regards

 

By the way, below is what is written on the cover of the converter

 

By the way, below is what is written on the cover of the converter
View attachment 306149

The info you need is right there including the modbus register command.

 

I know. Bloody thing does not seem to work.
Ho wan I check this via PC?

 

I know. Bloody thing does not seem to work.
Ho wan I check this via PC?

Use an o-scope or one of those $10 USB logic analyzer to look at the bus for proper signals sent and received. Be sure the power pins are connected correctly and measure the A B wires for bus proper termination with the system unpowered.

 

I used a USB to RS485....
No UART terminal software was able to get the data from the register.
I can connect. I believe this things needs specific address to read the data register
Try to find a software that can talk to this.

 

If I use address2, I get timeout
but on address 1, I get in sufficient data rcvd

 

Well..Guess what?
The address was wrong.
Had to contact manufacturer and they sent the correct address and software to test it.
Go figure.