Temporary instability problem of continuous acquisition behavior when using the PCI NI 6534 in Windows 10

[johnrojas]

Hello friends,

I'm running an acquisition continuous application implemented in Visual C++, for which NI 6534 (PCI interface) with the driver NI-DAQmx 19.0 for Windows 10 is used. In the program every data block reading is configured by calling a CallbackFunction as follows Config_DAQ_Event_Message(m_DeviceNum,1, "DIGRP1",1,m_SizeofBuffer,0,0,0,0,0,0,(u32)&CallbackFunction), then when the CallbackFunction is executed the data block is read by the instruction if(DIG_DB_Transfer(1, 1,(i16*)TempAcqNIBuffer, m_SizeofBuffer)). The acquisition time of every block is calculated in 2.56 seconds, but when the time of every block is monitoring continuously I observe critical variations around this average time, from 1.1 sec to 3.9 sec, as shown in the graphic Block_time_Windows10_PCI_NI_6534_2_56sec.jpg.

In another scenario, when I changed the NI 6534 by the NI 6537B (PCIe interface) with the same driver and S.O., but with different functions to configure and acquire data block, the acquisition time of every block is more stable as shown in the graphic Block_time_Windows_10_PCIe_NI_6537B_2_56sec.png. 

In the first scenario, with the NI  6534, we take some solutions such as changing the execution mode to work in real-time in the application, even we raise the privileges that manages the hardware interrupt NI 6534 but we get the same unstable temporal behavior.

Are there any solution to work stably over time using NI 6534 in Windows 10?, I would appreciate any response,

Thanks