Help! Can M90 communicate to a Raspberry Pi via RS232?

[curiousiya]

Hi! I'm new to this forum so please be patient with me.

I'm trying to automate a cable cutter that uses Unitronix M90.

I want it to load a certain length and quantity when I scan a barcode.

Have any of you sirs connected M90's RS232 to the serial of Raspberry Pi?

Is there a set of code to send to the M90 for it to be able to communicate?

Sorry the machine is always running and I need data before I can try and test. 

[Joe Tauser]

I have talked to an M90 via RS232 from a PC, so you can certainly do it with a Pi.

Code has to be added to the M90's program to receive serial data as you describe.  You will need the M90 program for this - do you have it?

An M90 is not an expensive piece of hardware - I would recommend you get another one for testing and then you'll have a spare.  You'll also need a serial cable - part number RS232-CBL.  You should be able to upload the program from the M90 - there wasn't a lot of copy protection in place when these were made.

Joe T.

[AlexUT]

Raspberry PI serial ports are TTL (unipolar, low level).

You cannot use it for direct connection to other non-TTL devices.

Communication to PC use RS232 bipolar signals.

You have to use any available TTL-to-RS232 converter, either shild, HAT, or other one.

When hardware interface will be connected, you can continue with PI and PLC programming.

You can read details at next link:

https://elinux.org/RPi_Serial_Connection#:~:text=The Raspberry Pi serial port,the other%2C and vice versa.

B.R.