Phantom Lord

Hi, I downloaded the rsspecan drivers from the Rohde & Schwarz website and followed the "How to use the Rohde and Schwarz LabVIEW instrument drivers" guide to install them correctly. I unpacked the zip file in 'C:\Program Files\National Instruments\LabVIEW 2009\' thus placing the correct files in user.lib and instr.lib folders; Upon starting LabVIEW, the express VI "Configure rsspecan_core_attribute_express.vi" is installed correctly under 'User libraries'. In the Instrument I/O palette however, no rsspecan driver is visible although there is a massive amount of added folders in the instr.lib folder. . Any ideas on what causes this? I installed several other instrument drivers and never had problems so far... Also, the rsspecan seems a pretty elaborated driver so it surprises me I'm having problems with it. any help would be greatly appreciated. Best regards, Filip

The code after the button start measurement is placed because earlier I had more start buttons. But now to the point. The two while loops in the code I sent to you are loops which where originally for loops. So, I thought: I'm gone replace them by while loops so that it is possible to step out of the loops. Because, when using the for loops I had exactly the same problem. After replacing them I saw that the problem wasn't solved. This program is written for a stepper motor controller and a receiver. The program you see is made to scan every point of a given surface with an adjustable step. At each point the motors have to stop and a measaurement must be made. For the measurement another subVi is called. With the "reference" I made of the button 'stop measurement' it is possible to step out of the subVi. But then comes the big problem: There will be a motion to the next point and a measurement starts again, thats because I can't step out of the while loop. One of the other remarks of you is that i didn't use numeric values: This is a good remark, but the controller reads the code which is sent to it in string format. And so... My question to you: Do you see a solution to completely stop the masurement. With other words to step out of the while loops. regards, Sacha

We have tried using the for loops, but doesn't the problem remain the same then. The reason for using string controls is they are used as a string to send commands to our CNC controller. I can't answer you regarding the code used there, it is written by my student, i am just helping him out where he gets stuck . Seems like it has something to do with adding more controls that perform a certain action. But we are trying out some of the hints you gave us right now.

Thanks for the replies. In attachment I put the code as it is. We do not have labview 8.5 (yet). We did break the while-loops in the subVIs by using references to the stop. Probably you won't be able to execute the code without the external equipment, but maybe you can have a look at it as it is. regards,Filip QUOTE(Aitor Solar @ Nov 20 2007, 10:36 AM)

Hi all, We built a labview program to control a triaxial scanner. There is a subVI that initializes an automated scan, which means it calculates steps in the X and Y direction depending on the dimensions you enter. First we used a for-loop inside a for-loop to move first a few times in the X-direction, then change Y, move in X-direction again etc... Now we have to be able to stop the scanner at anytime. As I read in this forum, a for-loop can't be stopped until it reaches the final iteration. That's why we changed this to a while-loop inside a while-loop. Unfortunately this also doesn't seem to work. Activation of the stop-button is always ignored (not seen). Probably this has to do with the fact some subVI's are executed inside the while-loop. Is there anyway of jumping unconditionally out of these while-loops (without terminating the program and labview that is)? We thought about event structures but this doesn't seem to work either... regards Filip

Hello, Ok, this needs to be finished tomorrow so can somebody please help me out? Is it possible to write data coming from my different subVI's, executed sequentially, to the same spreadsheet file? Well, I know that it is possible , but e.g. my waveforms are all connected to the same graph on the main VI through references, so is it possible to connect the reference of every subVI's waveform graph with the value property to build array and then export to spreadsheet? And it would be good if this could be connected to the boolean "write report". Thanks a lot

hi, well, that looks a lot easier to do. thank u very much. I'll surely use it. cheers Filip

Hi, Thanks for the response. Did make sense i guess as the time out error dissappeared. But it still not working though. The serial write keeps on only reading one byte. but I guess I know where the error is, just not how to solve it. Think it has something to do with the conversion. I included this VI as well now. Seems the boolean array is converted to only one character instead of two. Looks like it only takes the first byte or something to convert. Someone else gave me this VI but it was intended for one byte, but I don't know what to change. Any ideas? Meanwhile I keep searching Thanks again

Hi, I'm trying to send two bytes to an FPGA with the vi in attachment. The bytes are sent to a virtual com port which is actually an USB port, but this is handled through an FTDI chip. When two bytes are sent, the FPGA sends 11111111 or

Thank you very much! This works perfect. :worship:

I am using NI-VISA. The FPGA controls the FTDI chip i.e. it collects the data if available on the FTDI (when RXF goes low) and controls the RD and WR of the FTDI chip. This is done by VHDL code. The byte is then used to control multiplexers on a pcb that's an extension of the FPGA. The byte sets the enable and control lines of the multiplexers. When the byte is read by the FPGA and sent to the multiplexing logic, a byte is automatically sent back to the FTDI and thus LabVIEW to tell the data has been written. I hope this is sufficient?

Hello, I am using the FTDI chip FT245BM in combination with an FPGA. I have communication between LabVIEW and the FPGA (leds are lighting up) but when I want to send a byte (so 8 bits e.g. 01010101) then it is always the ASCII code of the last bit (in this case 1) that gets presented at the leds. So when I send the letter A, also one byte is sent. How can I send a byte with "separate bits", so I can see the bits I sent on the leds? Thanks Filip