when i use seven segment dispaly it does not work why?
it work fine with hex dispaly
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multisim
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Repeat triggered DO sequence
I have an NI-6251 that I've set up to output a sequence of digital patterns based on an incoming trigger line (used as the "clock" signal). For example:
Input trigger 0: output line 0 set high
Input trigger 1: output line 0 set low, output line 1 set high
Input trigger 2: output line 0 set high, output line 1 set low
Input trigger 3: etc...
The problem I have right now is that I can't figure out how to tell the sequence to repeat itself. I can repeat the task a defined number of times by just writing these actions over and over again in the sequence, but if I end up with more triggers than there are entries in the sequence, then I get incorrect results. I only really need two actions in this sequence: one to set line 0 low and line 1 high, and the other to set line 0 high and line 1 low. Thus I want to generate a length-2 sequence and then tell the task to automatically repeat itself (so that after doing action 1, it resets its internal index and goes to action 0). Similarly, if I had a task with three separate lines that I wanted to individually toggle, then I'd only need 3 actions in the sequence if only I could figure out how to get the sequence to repeat.
Unfortunately I haven't managed that yet. I found the "Repeat Mode" property, which looks totally perfect except it's deprecated and not available. Surely there must be some non-deprecated equivalent?
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sbRIO 9606
Dear all,
I am quite new with Labview and I have recently received a SB rio board 9606 +.
I followed the guidelines with respect to its setup but when I turned on the board, after some seconds, the led number still blicks twice per cycle.
I checked on the manual and i got :
"The device has detected an error in its software. This usually occurs when an attempt to upgrade the software is interrupted. Reinstall software on the device. Refer to the
Measurement & Automation Explorer Help for information about installing software on the device."
Besides I find it very strange for something brand new, i could find anything there which guides me to solve my problem. How do i reinstall the software on the device?
Thank you for attention.
Regards,
Pedro Santos
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Digital Trigger Output with NI 9403 and NI cDAQ-9178
Hello All,
I am currently using a NI cDAQ-9178 chassis, with a NI 9403 module, and a NI 9923 connector block. I have a pulse wave that is connected to PFI0 of the chassis to use as a trigger. I have connected a wire to the DIO channel 5 and it has a voltage divider conencted to it to reduce the output voltage from 5 V to 3.3 V. I want the DIO channel 5 output to be 0 V every time when the trigger goes to 0 V. In this system, a low bit pattern is 3.3 V and a high bit pattern is 0 V. Attached are some pictures of the oscilloscope screen and my code. The purple/pink is the pulse wave and the yellow is the output connected to channel 5. As you can see, it does trigger low, but it skips one until it goes to 0 V. I want this to go every time and to not skip one. The number of times the for loop is executed is just a placeholder and will be modified later. Any suggestions? Thanks!
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PCIe-6536 Simultaneous Read and Write
I have an application where I need to simultaneously read 24 bits (Ports 0-2) and write 8 bits (Port 3), using an external clock. The way it is done now is I create a read task and I create a write task. I send my external clock to PFI4 and PFI5, because two clock inputs are required (one for read, one for write). And I send a trigger signal to PFI3 to start and synchronize the tasks.
However it is not working correctly. My clock is ~15MHz and the reads and writes are off by a random number of a few clock cycles. For example when I start writing out Port 3, the reading into Ports 0-2 will start 2 or 3 or 4 clock cycles later.
Is there a way that I can read and write simultaneously that will work correctly??
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Velocity measurement using 9401 mounted in 9174
I have an NI9401 in a 9174 chassis. I would like to measure the velocity of a bullet. I have 2 optical sensors, each that put out a 5V pulse when the bullet passes thru the beam. The only input should be distance between sensors and units (ft or m) and the output should be time in seconds and velocity in either feet or meters per second. This should be about as simple as it gets. I've been looking for an example .vi and haven't been able to find one yet.
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synchronize digital output AND digital input NI-USB 6343
Hello
I'm using NI-USB 6343 to drive 1 TTL device. This device can also output a TTL signal to indicate whether the gate is opened/closed.
I'm using Digital Bool 1 Line 1 Point. I was able to flip gate open/close in timely manner. But i Like to sync DI and DO properly.
I tried to throw in OnBoard clock but it was not successful.
Is there any way to sync DI and DOI using onbaord/hardware clock?
Any insight will be great!
Thanks!!
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Configure C Module Without Chassis
Hello Guys..
I'm just wondering if there's any possibility to configure or
Read/Write in C Modules alone,, without using CDAQ or CRIO chassiss..??
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Current rising when connect HSDIO
I have an evaluation board for AD6645. When I connected and turned on power supply, generators I begin see the digital code on output digital pins of AD6645 through oscilloscope. Then I measure current which consumes AD6645. It's OK. And then I connect to output connector J2 HSDIO PXIe-6556 and the current (net +3P3V) is rising from 80 ma to 160 mA. Has anyone encountered a similar problem (current is rising when connect to digital pins of IC HSDIO)?
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RIO - Channel to channel skew
This has been a difficult query to answer through my usual routes, so I'm hoping this finds a domain expert in the likes of Spex or similar.
I use a lot of R series and RIO devices for test and measurement systems. Mostly, the requirements for these are in the analogue domain, with relatively low speed requirements (10, 20 MHz) in the digital domain. My current favourite device is the sbRIO 9636, which is perfect for my sort of industrial processes - I can integrate it into a rackmount system without worrying about bulky cables, and usually it's able to do most of what I'm hoping it can.
I have a new process coming up which will require a greater channel count in order to accommodate analogue and digital DUTs. In addition, the digital clocked outputs it will have to measure will be more like 50 MHz max. Because I'd like to stick to the sbRIO if I can, my ideal solution would be similar to a 9626 with a 9693 with additional C-Series modules, but with access to additional DIO on the RMC. And yes, I'm aware of what that system will look like (without the need for a custom RMC 
) I'm pretty sure that even at RMC digital inputs, I can probably get to 44 MHz (with no headroom for Nyquist, which isn't so much of a problem). I know RIO devices often quote 80 MHz as the input speed, but I'm also aware that most advice seems to suggest applications beyond 5 to 10 MHz carefully consider timing.
Previously, I discounted using a cRIO with 9403s for the high speed digital because of uncertainty over the channel-to-channel skew and propagation between the input pin and the FPGA. If I could be guaranteed a fixed latency between pin to FPGA with a finite but small skew, I would be comfortable with that, as I care most about missing edges and synchronisation between mutiple inputs from the same device. These days, especially with the newer Zynq chassis making them more attractive, it's worth revisiting...but still those questions remain about channel-to-channel skew.
For what it's worth, PCI/PCIe devices are out due to a compatibility issue with other hardware. USB devices are out due to a lack of robustness within my test environment (whether due to lack of strain relief on most USB connections or because Windows likes killing USB devices from time to time). I can't justify moving to FlexRIO due to cost either. With access to a variety of R series and RIO devices, I know I can benchmark some of this, but it'd be nice to hear from someone vaguely in the know.
So, after a long ramble, my questions:
1. What's the channel-to-channel skew like on board level IDC DIO for sbRIO devices (4x on 9626, 28 on 9636)?
2. What's the channel-to-channel skew like on C-Series modules through an RMC (e.g. a 9403 connected to a 9693)?
3. What's the channel-to-channel skew like on C-Series modules through a cRIO chassis (e.g. a 9403 through a 9068)?
4. Are there any other options I'm missing?
I'd be happy to explain more about my process requirements away from the fora, if helpful.
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Abrir puerto serial
Hola
Me he topado con un pequeño problema.
Lo que intento hacer es comunicarme con u modulo de pago, esto con el fin de mandarle comandos de manera serial y ver que los leds esten funcionales.El problema surge puesto que no se manda el comando como tal, o eso es lo que yo pienso ya que el modulo no hace absolutamente nada.
En la imagen podran ver el codigo tal cual lo tengo, al igual el comando que le estoy enviando (Este debe ser caracteres de bytes).
La respuesta de la tarjeta es una muy diferente a la que me deberia dar por eso es que pienso que no se esta enviando el codigo correctamente.
Me podrian ayudar a ver cual es el problema?
Gracias
Saludos
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NI 9472 with 9171 to control a 24V Solenoid Valve
1) I am trying to connect a solenoid valve to a NI digital module 9472 with a USB DAQ Chassis 9171. I have verified the voltage signals and used NI Max to turn the valve on and off. Now I am trying to find a VI to do this operation i.e. turning on and off one solenoid valve.
I found some example code such as: Digital - SW - Timed Output.vi (attached). I modified the code a little bit to interface the digital channels from the module. Such as in the DAQmx tasks, I have created a "task in" channel to read the signal from specic port from 9472, and as the very same port as the i/o lines . But I keep getting an error -200463 message:
"Specified read or write operation failed, because the number of lines in the data for a channel does not match the number of lines in the channel.If you are using the Digital Waveform datatype, make sure the number of lines in the digital waveform matches the number of lines in the channel. If you are using boolean data, make sure the array dimension for lines in the data matches the number of lines in the channel.
Number of Lines in Channel: 1; Number of Lines in Data: 8"
I am very new to Lab view, so any help in this will be greatly appreciated.
Vikram
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MyRIO UART
Hi,
I am a new user of NI myRIO. I am trying to reproduce the UART demo program. The project is attached.
In the https://www.youtube.com/watch?v=0FMnkFDsGQs, the UART works perfectly.
However it doesn't receive any characters in my program. I set both the write and read block with same frame parameters.
RIO device works also fine.
Somebody can tell me what has happened to my program (UARTVI.vi)?
Thx
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NI 9237 Input
Hello,
I am trying to understand if I can connect a 6-axis force sensor(full bridge) , composed of 6 wheatstone bridges with a single output cable, to the component NI 9237 present in my CompacRio configuration or if I can just convert the signal and use a simple current analog input module like the NI 9208. Are there any advantages in using a bridge adapted module?
Thanks,
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Generating Frequency Specific Digital Pulses
Hello All,
I'm using a myRIO with Labview 2014 to control some stepper motors. I have both the drivers in single step mode, where a single digital high signal will result in a single step. I'm planning on controlling the overall motor speed by controlling the frequency of digital high signals. My first thought was to use the PWM express VI however I am unsure as to the duration that this VI runs, in other words if I had the express VI and nothing else on the block diagram and I input a frequency of 40 Hz, for how long will it generate the 40 Hz pulse? One period or continuously until the VI is stopped?
My second question is I've read that the lower limit of frequency able to be generated by the PWM express VI is 40 Hz, but I may need to go as low as 10-20 Hz in some cases. What would be the best way to create a square wave digital signal with frequency as an input and wire it to a digital output? The standard digital output express VI on the myRIO accepts boolean true/false for digital high and low so could I do this with a conversion? I'm quite new to labview so any pointers would be much appreciated!
Cheers,
Ben Sia
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How to combine multiple digital inputs for reading?
Hi Fellow Labview users,
I just started using LabView and I'm very new at it. I know the basic understanding of how it works and got something to work but I need it to be more efficient.
I'm using Measurement Computing's USB-DIO96H DAQ, which has 96 digital inputs. I use the DAQ to acquire relay activations and record the number of times the relays flips.
Basically I created one digitial input read, and then copy & pasted it 95 times... it works but I know this is not the best way to use LabView.
How can I change the digital input (dev0/1stPortA/Di1) to be multiple so that it iterates through all 96 channels without copy and pasting the same diagram over and over?
Leon
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6556 SPI Communication -- WireLength Matters?
Hi All,
I'm using HSDIO 6556 lines for 4-wire SPI communication of digital device whose output is a 16-bit digital output from the ADC. We need to use SPI 4-wire communication to talk to the digital registers in order to acquire the 16-bit digital output from the ADC.
I'm using a bread board to hold the device, and connecting the SPI lines through wires. The power-up of the device are done through wire's using SMU channels.
The problem I'm facing here is, I'm able to read the 16-bit digital output from the ADC using shorter wire length of approx 10 inches long. But the same setup, while trying with wire length of 1 to 1.5 meter long, I'm not able to acquire the raw data from the ADC correctly. There are missing bits in the data.
I'm using Labview2013 for this HSDIO acquisiton and generation. I have tried with the HSDIO properties of "Delayed Data Active Event" in order to compensate for the round trip delay. But still I was not able to acquire the data correctly.
So my question is, Whether the wire length really matters for SPI communication? Is there any limitation on the cable length during HSDIO acquistion and generation? Or whether the HSDIO calibration is limited to particular length only?
Kindly help me in this regard.
Thanks & Regards,
Pramod Kumar
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Hsdio pxie-6556 - Write jtag command -> wait ack --> write new command
Hi all,
I am trying to write into a dut memory using jtag commands. Each command write one byte in the dut memory. At the moment I will need to write 5k bytes
I am able to create the waveforms (using the Labview jtag library).
The problem is that the dut works at 5MHz clock and after each command there are a ack pulse.
I must wait for this pulse before send another command.
How I could implement this waiting time?
Hardware: Pxie-6556
Software Labview 2013
Tks,
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How to improve parallel voltage signal on multiple channels
Hi there!
I have a 0-10VDC signal coming from a Turck MS25-Ui rotation montior which was being read by one input channel (differential) of an Eaton XIOC-4AI-2AO-U1 analog in/out module. Impedence 40kOhms.
I paralelled with that two channels from the NI 9205 using the same common. These are 10GOhms each.
Voltage signal on the Eaton PLC is going bye-bye. Is it because the impedence difference? I thought voltage could be paralelled without loss regardless of load...
Is there a simple way to fix this? Plenty of room for extra hardware if needed...
I don't HAVE to split the signal three ways -- I was using two channels on the NI 9205 because I want to sample the same signal at two different rates and don't believe I can create two tasks for the same input using DAQmx. That's probably wrong too, but I'm new at this.
Thanks very much for your support!
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PC-DIO-96 DAQ ERROR 55135
Hello,
I am trying to migrate my test platform from XP to WIN 7, but the PC-DIO-96 I can't see on the NI-MAX application.
I tried with NI-DAQmx 9.7.5, 9.8, 9.9 and NI-DAQ traditional 7.5, but I can't see the device PC-DIO-96 on WIN 7.
Someone that provide me any information??
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