Opensuse Linux and the Prologix GPIB to USB converter
This page describes how to control the Prologix GPIB-USB converter on an Opensuse 10.3 linux system using Labview 8.2.
Everything described below is done as root; once it works you should give normal users read and write access to /dev/ttyUSB0 and continue to work from your normal account.
Check that the converter and the kernel work together
- Plug in the USB cable with the converter.
- Check if the right modules get loaded:
- $ lsmod | grep ftdi
ftdi_sio 37128 0
usbserial 35252 1 ftdi_sio
usbcore 123756 6 ftdi_sio,usbserial,nikal,ehci_hcd,uhci_hcd
- The device should show up on the USB:
$ lsusb: Bus 001 Device 004: ID 0403:6001 Future Technology Devices International, Ltd 8-bit FIFO
- and a new device node should be created:
$ ls -l /dev/ttyUSB0
crw-rw---- 1 root uucp 188, 0 Dec 4 15:39 /dev/ttyUSB0
- $ lsmod | grep ftdi
- You can check if the converter works correctly by using the program kermit (package ckermit):
C-Kermit 8.0.211, 10 Apr 2004, for Linux
Copyright (C) 1985, 2004,
Trustees of Columbia University in the City of New York.
Type ? or HELP for help.
(/root/) C-Kermit>set line /dev/ttyUSB0
(/root/) C-Kermit>set terminal echo on
Connecting to /dev/ttyUSB0, speed 9600
Escape character: Ctrl-\ (ASCII 28, FS): enabled
Type the escape character followed by C to get back,
or followed by ? to see other options.
Prologix GPIB-USB Controller version 5.0
Communicate with the converter using National Instruments VISA 4.2
prepare the system for installation
- Make sure you have the necessary packages installed (your version numbers will probably be higher than mine due to security updates).
$ rpm -qa | grep kernel
$ cd /usr/src/linux
$ make cloneconfig
$ make modules_prepare
$ make modules
(the last step is according to the NI-Visa documentation not mandatory, it avoids some warning messages)
- Download the newest NI-VISA for linux (at the time of writing version 4.2) from the National Instruments website.
- Run the INSTALL script from /usr/src/linux
- check for error messages, especially in the NI-KAL post installation script.
- create/edit /etc/profile.local with:
communicate with the converter using visaconf and NIvisaic
- run visaconf from the command line
press the add static button
select Local Serial Port as the new interface
set the binding: /dev/ttyUSB0
set an alias like prologix
change the interface number to 5 (or another non used number)
The other settings like Baudrate, parity, stop bits and flow control can remain unchanged; they are irrelevant.
After pressing OK the main window should look like Figure 1.
If you now plug in the device and press edit on the ASRL5::INSTR, the Resource editor (Figure 2) window should show the state of the device as ready.
- Start NIvisaic
if ASRL5::INSTR shows up you are ready to use the device under labview.
However there seems to be a bug in the NI software which only shows up if your computer has no generic serial port like some laptops:
An error message pops up:
unable to find resources using expression "?*"
Return status code 0xBFFF0011
Status name: VI_Error_RSRC_NFOUND
- Workaround: create a hardlink:
$ rm /dev/ttyS0
$ ln /dev/ttyUSB0 /dev/ttyS0
$ ls -l /dev/ttyS0
crw-rw---- 2 root uucp 188, 0 Dec 7 10:17 /dev/ttyS4
Now NIvisaic looks like Figure 3; both entries will work under labview.
Communicate with the converter using Labview 8.2
- find in the examples the "Basic Serial Write and Read.vi" (Figure 4)
- set the VISA Ressource name to ASRL5::INSTR
- open the Visa Configure Serial Port SubVI and set the button Enable Termination Char to off. (Figure 5)