RTS/DTR as source for opto?

[rdam]

How can I use RTS/DTR (RS232 -12V/+12V) as source for optocoupler on a multimeter?

[Chris_Rake]

Can you give a few additional details about your project?

[rdam]

Hi Chris,

I want to read a multimeter. For the galvanic isolation (it is a opto coupler) i need a power supply.

The handshake line is not in use, thats why i want to use the RTS/DTR line. In Q-Basic you canG#‘Ài haven't find this parameter.

Thanks a lot for your answer!