Can DAQPad-6507 use its 8255s in MODE1?

[Janos 53]

Hi,

I studied some digital I/O examples. I found that daqevt8vc.c is closest to what I want to do. I have, however, some problems here.

1./ According to the comment at the beginning:
/* DAQ EVENT 8 generates an interrupt when the data from a specified
/* digital port/line is ANDed with DAQTrigVal0 and equals DAQTrigVal1.

The example compiles fine, but does not generate an interrupt.
(in another program I can set up the device and with the call to DIG_In_Prt() I can read the content of register 0, so I am pretty sure Line 0 goes high when I change the switch settings. Unfortunately, within the cycle I cannot read Reg0, because it is already used be DIG_Block_In.)
Could you please send me an example program which works a
s stated?

2./ Even if it works:
from the comments in the sample as well as from the fragment of the help file that option 8 "require the processor to examine each data point as it is acquired or transferred" comes out that the 8255 in 6507 works in MODE0.
What I need, it is MODE1 where a strobe signal generates an interrupt, as described in the appendix B of the 6507 manual. Is this possible with this module?

3./ I need to read out a nuclear ADC which fires on random events. I need to read out when it produces a strobe signal and I need to read it out an infinite number of times. Can you please advice, how can I reach this goal with the module? (I accept a sample program, pseudo code, documentation hint or anything.)

Thanks for any help

Janos

[ThorstenRo]

Hello Janos,

The documentation for the DAQpad-6507 shows that it does allow for data transfers via interrupts. The Traditional NI-DAQ function Set_DAQ_Device_Info also allows you to change the mode of data transfer.

I hope this helps.

Regards

R.T.
NI Germany

[Janos 53]

Hello Thorsten,

thanks for replying.

Well, I am not sure it is the solution.
First of all, Traditional NI-DAQ function Set_DAQ_Device_Info is not listed for my device, so either it is a bug in the documentation or is really not usable for my device.
(I have Get_DAQ_Device_Info in my list).
In addition, under "Data Transfer Methods: Set_DAQ_Device_Info
" I do not see my device, which means: "If your device does not appear, none of the data transfer modes are applicable." And, my device is *not* on the list.
So, I *guess* it is not for my goal.

Otherwise, even if it is usable, the purpose of the function is
"You can use this function to select the data transfer method for a given operation on a particular device."
And, in Config_DAQ_Event_Messag
e I read:
"DAQEvent = 3 through 8: These DAQEvents are for interrupt-driven data acquisition only.", i.e. I even could not change the data transfer method.
What I really need is something different.
In the meantime I think I found some solution (I am not sure if the real one), see my answer to my own question.

Thanks for trying to help.

Best regards

Janos