USB 6009 Add Analog Input, Error 200077

Hey everyone,

I am using the Data Acq Toolbox version 3.1 (r2012a) with a NI USB-6009 running DAQmx 9.5 drivers. The device has 8 analog inputs if used in single ended mode, and 4 analog inputs if used in differential mode.

I am programming through the session based interface. If I attempt to create a session and add channels however, I am only able to add the first 4 channels since they by default are added as differential. If I try to add a 5th channel, I get error message 200077.

See the code below:

>>  daq.getDevices

ans = 

ni: National Instruments USB-6009 (Device ID: 'Dev1')
   Analog input subsystem supports:
      8 ranges supported
      Rates from 0.1 to 48000.0 scans/sec
      8 channels ('ai0','ai1','ai2','ai3','ai4','ai5','ai6','ai7')
      'Voltage' measurement type

     Analog output subsystem supports:
        0 to +5.0 Volts range
        Rates from 0.0 to 0.0 scans/sec
        2 channels ('ao0','ao1')
        'Voltage' measurement type

     Counter input subsystem supports:
        Rates from 0.0 to 0.0 scans/sec
        1 channel ('ctr0')
        'EdgeCount' measurement type

So I know that MATLAB recognizes all 8 channels of the DAQ. However, when I create the session and attemp to add all the channels, I get this:

>> s=daq.createSession('ni'); s.addAnalogInputChannel('Dev1',0:7,'Voltage')

NI Error -200077:
Requested value is not a supported value for this property. The property value may be invalid because it conflicts
with another property.
Property: DAQmx_AI_Min
Requested Value: -20.0
Valid Values Begin with: -10.0
Valid Values End with:  10.0

Channel Name: Dev1/ai4

Task Name: _unnamedTask<44>

Status Code: -200077

I understand why it's giving me the error...mainly because it's trying to add all 8 channels as differential inputs. Is there any way to specify when creating channels in the session based interfaced to add them as SingleEnded? I know I could modify the InputType subproperty of the Channels property, but that is only possible after the channel has been added

[bym]

I don't have the data acquisition toolbox, but it appears you are trying to add a channel (Dev1/ai4) who's minimum is -20 volts where only ± 10 volts are supported

[Walter Roberson]

No, Donald just requests "Voltage". Which is a valid property for both analog channels and differential channels. Donald does not specify a voltage range, and has no access to the voltage range setting until the channel object is constructed.

The channel being complained about is ai4, the fifth channel -- a channel that only exists when the devices are in single-ended mode. But Donald cannot switch them into single-ended mode until the object is already created...

[Donald Bucci]

--proecsm

That's sort of correct. The channel limits of the USB 6009 are -10 to 10V in single ended mode. Hence when it's in differential mode...these translate to a min and max of -20 and 20V respectively. It's basically trying to set the thing in differential mode and the error happens when it tries to set the corresponding range that goes along with differential.

[Donald Bucci]

Anyone else have any ideas? I know there must be a way to work around this, other than just downgrading to the legacy code.

Answer 1

[Donald Bucci]

Figured this out. I am using MATLAB 64 bit. Downgrading to 32 bit and performing the original tasks don't present this issue. Is there some way I can forward this to MATLAB's bug department?

Answer 2

[Walter Roberson]

This is a hack, but...

Construct the object with channels 0:3. set() the single-ended property of the resulting object. Now channels 4-7 should come into existence, so add-channel those in as well.

[Donald Bucci]

So in doing this, here is my output:

>> s = daq.createSession('ni'); s.addAnalogInputChannel('Dev2',0:3,'Voltage')

ans =

Data acquisition session using National Instruments hardware:

Will run for 1 second (1000 scans) at 1000 scans/second.

Number of channels: 4

index Type Device Channel MeasurementType Range Name

----- ---- ------ ------- --------------- ---------------- ----

1 ai Dev2 ai0 Voltage (Diff) -20 to +20 Volts

2 ai Dev2 ai1 Voltage (Diff) -20 to +20 Volts

3 ai Dev2 ai2 Voltage (Diff) -20 to +20 Volts

4 ai Dev2 ai3 Voltage (Diff) -20 to +20 Volts

>> set(s.Channels,'InputType','SingleEnded')

>> set(s.Channels,'Range',[-10 10])

Viewing s.Channels yields:

Number of channels: 4

index Type Device Channel MeasurementType Range Name

----- ---- ------ ------- ------------------- ---------------- ----

1 ai Dev2 ai0 Voltage (SingleEnd) -10 to +10 Volts

2 ai Dev2 ai1 Voltage (SingleEnd) -10 to +10 Volts

3 ai Dev2 ai2 Voltage (SingleEnd) -10 to +10 Volts

4 ai Dev2 ai3 Voltage (SingleEnd) -10 to +10 Volts

Which seems right, however I then go to add the other channels and the same error results:

>> s.addAnalogInputChannel('Dev2',4:7,'Voltage')

NI Error -200077:

Requested value is not a supported value for this property. The property value may be invalid

because it conflicts with another property.

Property: DAQmx_AI_Min

Requested Value: -20.0

Valid Values Begin with: -10.0

Valid Values End with: 10.0

Channel Name: Dev2/ai4

Task Name: _unnamedTask<2C>

Status Code: -200077

[Walter Roberson]

Sorry, just saw your response now.

Unfortunately I do not have any suggestions at this point (other than asking support)

Some day I'll get the DAQ toolbox and a system to run it on and some devices to connect to it...

Answer 3

[Manisha]

Look at this bug report for this issue.

Thanks,

Manisha