Configure GENERAL_DAQ_EVENT activeX object under Visual Basic

[Martoh]

Hi,
I'm using a 6527 Digital I/O interface with NI-DAQ under visual basic. Each line is configured I or O independently of port.

How can I use the GENERAL_DAQ_EVENTn activeX and how must I configure the .ChanStr property to use it with that board ?

[Raecine Meza]

The documentation for the NI-DAQ function Config_DAQ_Event_Message will tell you how you can use the different event options and also how to set chanStr. For Digital Input, you use DIn where n is the channel number you are specifying.

There is a tutorial in Developer Zone titled "An Overview of DAQ Events and Occurrences" that you might also check out.

[PlGM]

None of NI documents describes how to configure the digital channel in detail (only analog examples).

Could any one tell me about:

1) How to configure the digital channel parameter chanStr to use 0.3 in 6527 (Line 3 in port 0)?

2) How to configure the DAQEvent and DAQTrigVal0/1?

(I tried all of combinations about the parameters above to modify the example code in event1 VB project and failed.)

Thanks.

[Travis G.]

Hello PIGM,

The document titled Traditional NI-DAQ C Function Reference Help (located under Start >> Programs >> National Instruments >> NI-DAQ >> Traditional NI-DAQ Reference) contains some good documentation about how to configure a digital channel.  Specifically, check out the help for the function DIG_Change_Message_Config, which has the following description of how to configure chanStr for digital lines and ports.

Value of riseChanStr	Meaning
0.0	port 0, line 0
0.0:7	port 0, line 0 through 7
1.(0,3,5)	port 1, lines 0, 3, and 5
1.0:5,2.1:4	port 1, lines 0 through 5 port 2, lines 1 through 4

I'm assuming that you are trying to configure your NI PCI-6527 to produce an event when a change is detected on one of the digital lines.  Take a look at the following example program for an idea of how to do this.

In VB 6.0:  Using Change Notification with the NI 6527 in Visual Basic

In C:  Using Change Notification with the NI 6527 in CVI

I hope this helps!

Regards,
Travis G.

[PlGM]

Thank you for your response.

(1) This message is about how to use General DAQ Event Control (ActiveX) in VB, So could you tell me how to use the digital channel in the the control?

(2) I knew how to use "Change Detection" for 6527, please refer to: http://forums.ni.com/ni/board/message?board.id=70&message.id=1053

(3) I found some information in NI web site about the ActiveX (http://digital.ni.com/public.nsf/allkb/728ffc53b2db747186256c94005f122c) that ONLY some devices can support the ActiveX, unfortunately my devices (6527 and 6024D) do not.

Please confirm it is true?

Regards

[PlGM]

Sorry about my typo, my devices are PCI-6527 and PCI 6024E (not 6024D)

[Travis G.]

Hello PIGM,

The General DAQ Event ActiveX Control contains configuration for a variety of different events.  The events the pertain to digital applications are events number 8 and 9, which are digital pattern match or digital pattern not match.  These events require a device that can perform the pattern matching function.  Your PCI 6024E series card does not support pattern matching, so you will be unable to use these specific event types with that device.  Furthermore, although the PCI 6527 supports change detection through the use of the DIG_Change_Message_Config, it does not support pattern matching events like the PCI 653x series of devices.

Regards,
Travis G.