Problem with testing DIO channels on PCI 6025E

[Maruthi]

Hello,
I am using PCI 6025E which has 32 DIO channels on it [DIO, PA, PB, PC each having 8 channels]. I am using 17 of the channels in my application but channels other than DIO i.e. PA, PB and PC do not work. When I test the channels it shows me an error. Please suggest as the card PCI -6025E has 32 DIO channels on it.

[rgharrison]

Hi Maruthi,

The PCI 6025E has two different hardware chips on the device to make up the 32 bits of digital I/O. The 8 DIO lines are native to the E Series boards and should operate as expected. The final 24 lines are from another digital chip called the 8255 PPI. It has 3 ports (A,B,C). Every time you reconfigure one of your ports, all three will reconfigure.

Therefore you might be getting into trouble if you need to reconfigure them. If you have already configured them and are just reading them, they act as standard dio lines. Application Note AN131 goes into some good detail on programming with the different National Instruments chips.

Where in specific in your application are you getting an error? After you have configured and are reading?


Ron

[Maruthi]

Sir,
I am using 17 DIO channels on my DAQ board using 8 on DIO, 8 on PA and 1 on PB ports. One on DIO is used to read the data from the shaft encoder and all the remaining 7 on DIO are configured as "Write to Line" and there is no error that I get with those channels. But on the PA and PB ports, I get an error as I configured them as "write to line". I They should actually be "Write to Port" as they are only port configurable. Could you please help me how to convert "write to Port" to "write to Line".

[rgharrison]

Hello,

PA and PB can only be writen as a group. Therefore, they all have to be configured as input or they all have to be configured as output. The functions you would use to configure the ports are:
iStatus = DIG_Prt_Config(iDevice, iPort, iMode, iDir);
And the following to read a port:
iStatus = DIG_In_Prt(iDevice, iPort, &iPattern);

Just make sure you do all of your configuration first. I hope that answers your question. Let me know if you have another question.

Ron

[Maruthi]

Sir,
I couldn't understand how to configure them as a group. I mean to say how do we do that on MAX. As line state is the most important thing in my application, I surely need the channels to use "write to line".and I want PA and PB to be configured in a group. I do know that PA and PB would only "write to line" as they are port configured, but I want to know if there is some way that we can program "write to port" to "write to line" as I want the channels to write the data to the line state.

[rgharrison]

Hello,

In MAX, this is not possible since MAX is just a testing and diagnostics program. You can only configure 1 port at a time in MAX and it resets your other ports.

What programming language will you use to write your application?

The NI-DAQ function call to output on a line is:
DIG_Out_Line (board, port, line, line_state);

Hope this helps.

Ron

[Maruthi]

Hello Ron,
where can I write the function call?? would you please let me know how should I do that. I can even send the vi that I am facing a problem at.

[rgharrison]

Maruthi,

Go to ni.com/ask and send NI an email describing your problem. Address the email to me "Ron" and it will get to me. I will be able to work with you via email.

Ron

[Maruthi]

Dear Ron,
I have some problems sending over an email. I would fix the problem very soon.

I am working on an application to control the components of a 4 cylinder 4 stroke IC engine using Labview. I have developed the application in such a way that I count the number of pulses from the shaft encoder per every revolution of the crank shaft and fire the cylinders accordingly. In this process I am configuring the 16 channels I need, for the output from the connector block/DAQ card to the components. Ideally the output is an analog output which would send +5V. But as the card being used is has just two, I have decided to take the help of the digital channels. So other than the analog output, I
need 8 from DIO and 6 from PA to configure. I have configured my DIO with no problem writing the data to the line state. But with PA, I need to configure the port and wrrite the data to the line which I am not able to do. As suggested by you, would you please let me know how to use the function call..
I can even send the VI to you.
Thanks for your help
Maruthi