usb to serial communication

[Priya.dharshini]

Hello everyone,

Im working on a project which has an device with rs232 port. I modified the basic Serial read-write VI. The program works fine with PC Serial port. But when I try to communicate with the same device through USB to serial converter (FTDI FT232RL FT232 USB TO TTL 5V 3.3V SERIAL ADAPTOR FOR ARDUINO BE0027) that's not happening and I get error message saying VISA read error. I searched forum for solution but still im at same problem.

pls help me out to solve with this problem.

Thanks.

[etuzuner]

Hi reva866, 

Can you share a code or a snippet so that we can help you?

Emre

[NIquist]

USB to RS232 Serial converters are getting better these days but you may still need to try a few different models if you're interfacing to older equipment.  What device are you attempting to talk to?

[Yamaeda]

RS-232 is a pretty loose and "sloppy" standard, so two devices which are both following the standard might very well not be able to communicate. I had a similar thing happen to me, where a JLink couldn't communicate with mu USB dongle, but worked with the motherboards serial port, but not on the next computers port ... So, try with a couple more. 😕

/Y

[Priya.dharshini]

Its the same vi from examples (Basic Serial Write & Read). The same program throughs "Framing Error during data transfer" error when I use USB to serial converter. What could be the reason for this. Pls help out.

Thanks

[daveTW]

I use FTDI- devices a lot and it's quite reliable. Look at my settings:

Driver Version 2.12 is quite new, but not essential

Klick this Button to configure the FTDI- Chip (the other settings are configured by your VIs settings)

These are my settings. No problems.

Are you using Handshake (XON-XOFF, DTR-DSR)?

[Priya.dharshini]

After doing these setting my error remains same (Framing Error). The baud rate, start bit and everything are set correctly. The problem Im mainly getting is that when I run it, sometimes it starts with a random symbol or character, and then it stops running and tells me I have a framing error. Sometimes as well, when I start it, nothing happens at all, and then after a little wait, it says I have a timeout error.

Pls help out

[etuzuner]

Hi reva866, 

Can you send/read data using a software like Putty? Like others say, you may have a problem not caused by LabVIEW.

I suffered a lot in the past because of the converters too. then I started to use this converter and I never had a problem.

Emre 

[Priya.dharshini]

The device has communication exe supplied by the manufacturer. with that also it is not communicating,

[Ben_Manthey]

There's a known bug with USB Serial convertors.

http://www.ni.com/product-documentation/52366/en/#182027_by_Date

It's supposedly fixed in VISA 15.0 but I haven't had a chance to test it.