01-09-2014 08:36 PM
Hi Everyone on the forum
I'm looking for the LabVIEW Driver for a GW Instek LCR 819.
I had been looking over ther internet with no luck, even the vendor doesn't have it
Currently working on ATE for an Oil Level Senor (Aerospace)
Does any one use it before... LabVIEW 2012
Solved! Go to Solution.
01-10-2014 08:17 AM
I don't see a driver from GW Instek either but I took a brief look at the programming manual. It should be pretty simple to write a driver for this. The command list is short and appears well documented. There are tools for developing drivers at http://www.ni.com/downloads/instrument-drivers/. Developing a driver is not as hard as you might think.
01-10-2014 10:26 AM
Thanks for the reply..
I already read the user manual fot the LCR, I saw the commands. I have hook up a null modem cable with a USB to RS232 adaptor (im using a laptop for
developping stage) I had been sending the COMU? commnad to see if the LCR answer back but nothing..
Do you thing the USB to RS232 works OK. I had problem using the USB adator to talk to DMM HP34401A, I didn't work, DMM don't like USB adaptor,
need to install a 2 RS232 PCI card to make them work..
Take a look to the image attach.
01-10-2014 10:40 AM
The first thing I noticed is that you are not sending any termination character after the command. Also, make sure that it really is a null-modem cable that is required.
I've had great success with USB-RS232 converters that use the FTDI chipset.
01-10-2014 11:04 AM
I will check the termination character..
I'm using FTDI Chipset also, USB-RS232-WE-1800-BBT_0.0 (Wire end Version) You did not connect the black and red cable, we don't need this
for RS232? only four cables?
01-10-2014 11:15 AM
the cable us null modem, I test the cable with a Agilent PS. and same USB to RS232 converter...
I'm missing something else...
01-10-2014 01:35 PM
I'm not having any luck talking to the LCR,
I send the command, No answer, No error either...
I saw the commands, there are not complicated. but can't stablish communucation
01-10-2014 01:43 PM
That is not the correct way to send termination characters. The basic example is set for '\' Code Display. You have to send the characters as that or on the block diagram, append them with string constants. Use can set a string constant for Normal, '\' Code. or Hex. Find the '\' Code or hex value of the termination characters.
01-10-2014 02:41 PM
I'm a litte confuse right now..
I have set the window as Normal display and send COMU?.
But you mean to add "\" constant...?
Getting frustated... all day with same issue...
Thanks for your help..
01-10-2014 02:53 PM - edited 01-10-2014 03:01 PM
You need to add a termination character(s) to the command string. Setting the display to Normal does not allow you to append any special characters. The default of '\' Codes display does allow for special characters. For example \r for carriage return or \n for a new line. The termination characters for your instrument are a bit odd. Instead of trying to use '\' Codes, it may be easier for you to use the concantanate string function on the block diagram to append the termination characters as a string constant. I would suggest setting this string constant to hex display or using a U8 array to enter the decimal/hex values of the termination character and then a Byte Array to String.
Before doing all of this, have you tested communication with a terminal emulation program such as Hyperterminal?
Edit: I should have looked up those scan codes before answering. A ctrl J is a line feed (\n) and ctrl M is carriage return (\r) so return the string control to '\' Codes and add \n\r. You could also try \r\n.