RS-232 on sb RIO 9636

[Chupka993]

Hello!

I am using Sabertooth driver 2x25 and Single BoardRIO 9636. I am trying to send data to Sabertooth over RS-232 (need only Serial Write) and my question is should I use NI VISA driver for that? Also, what is the range of output voltage of RS-232 (because Sabertooth works at TTL level)? Could you please attach some simple example if you have?

Thanks in advance,

Chupka

[deceased]

Yes, you should use VISA for this, also the voltage level will be too high. You will need to use something like a max233 chip to drop the voltage down to TTL for your device.

[deceased]

Sorry I misread original post and thought you had a comapct RIO. I think the SB RIO uses 3.3V logic, but I am sure someone at NI can clarify.

[Sam_Sharp]

Same applies - the sbRIO 9636 has RS-232 ports so it will be RS-232 voltage levels. You'll need to use a line transceiver to convert it down to TTL levels for a microcontroller. In that case, you'd use NI VISA.

You *can* also implement the serial communications using the digital I/O lines and some FPGA code.

[Chupka993]

Sam,

thank You for Your reply. I have two more questions. 

Do I have VISA driver - how should I know that? (I have installed LV, LV RT and LV FPGA from the installation CDs that come with sbRIO 9636 Evaluation Kit)

When I make VI that contains VISA functions where I should make it - under RT, under Target, or...?

Thanks in advance,

Chupka

[Sam_Sharp]

Look in NI MAX - NI VISA is part of the device drivers list so you should see it listed under 'Software' in MAX.

The RS-232 port is on the RT controller, so the VI that uses the RS-232 port needs to be under the RT Chassis in the project.