inputs return minimum value

[studio_uk]

I have RTX, DDK and a PCI-6254

I've managed to get the interupts to work fine, it fills the FIFO and I an read the data back from the fifo via port commands, however, the data all returns either 0 or -32768 depending on which polarity I have selected. Any ideas why this would happen?

P.s.

Other technical info:

I have a 5v reference voltage applied to the connector block from its own 5v pin. The AI-Sense is set to 0v from the AI-GND pin. This has been checked with a standard volt meter so the connector is making good contact with the card otherwise it would not give 5v. Secondly I read from all 32 channels which all return the same value. Ive loaded the calibration data correctly and manual testing shows that the calibration data maps very well to my voltage range (-+ 10v) and all 16bits.

Any ideas?

Thanks

John

[DiegoF]

Hi John,

I replied to your other post before I saw this one...  I'll place the same information here in case anyone else is running into this.

The adcReset() function in the mseries examples used:

    board->Static_AI_Control[0].writeRegister (1);
    board->Static_AI_Control[0].writeRegister (0);

when it should be:

    board->Static_AI_Control[0].writeRegister (0);
    board->Static_AI_Control[0].writeRegister (1);

Also, the convert polarity should be active low for 625x devices:

    aiPersonalize (board,tMSeries::tAI_Output_Control::kAI_CONVERT_Output_SelectActive_Low);

Let me know if that works.

[eastf]

Hi DiegoF

        Thank you for your infomation!

        I'm Get the problem when use RTX,DDK,PCI6259 do AI job. I got the random value when I acq. a value using "aiex1.cpp" . If i active the adcret() function,i got the  same small error value. That confused me all night.

        when i modify the code as you say,all right .

       Thank u.

     su

帖子被eastf在04-28-2007 09:25 AM时编辑过了