Migrating an Application from E Series to M Series

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There are several important differences between E Series and M Series devices. Many of these differences are described in the "Major Differences Between E Series and M Series" KnowledgeBase. This document highlights some of the main differences that need to be kept in mind when moving an application from E Series to M Series devices.

Contents

Hardware and Connectivity

  • Most M Series devices retain the same 68-pin format as E Series devices with all of the same signals mapped to the same pins, with the following exceptions:
    • PFI 0 on an E Series device serves as both an analog and a digital trigger input. M Series devices have their own dedicated analog trigger inputs, APFI 0 and APFI 1; PFI 0 only can accept digital signals.
    • The pin corresponding to PFI 15 on an M Series device corresponds to a digital ground on an E Series device.
  • Some M Series devices have two 68-pin connectors. The first connector maps directly to the E Series pinout, with the exceptions listed above. The second connector is identical to the first, with the following exceptions:
    • AI <0..15> are replaced with AI <16..31>.
    • AO <0..1> are replaced with AO <2..3>.
    • DIO Port 0 lines <0..7> and Ports 1 and 2 (the 16 PFI lines) are replaced with Port 0 lines <8..31>.
  • Although the E Series and M Series pinouts are the same, the connector styles are different. M Series devices use VHDCI connectors, the same connectors as PCMCIA E Series DAQCards. PCI and PXI E Series devices use SCSI connectors. Because the pin mappings are generally the same, E Series test systems usually do not have to be reconfigured or rewired to use M Series devices, though the cables will need to be replaced. The end of these M Series cables that connects to accessories uses an SCSI connector, and therefore can be used with all E Series accessories. Refer to the "Cabling Options for M Series" KnowledgeBase for more information on what cables can be used.
  • If the M Series device has two 68-pin connectors, the first connector can be used with SCXI, SCC, and 5B signal conditioning control. Because the second connector does not contain PFI lines, it cannot be used with SCXI. The second connector can be used with the SCC and 5B signal conditioning options.

Software and Your Application

  • M Series devices are only natively supported with the NI-DAQmx driver. If your application is written using Traditional NI-DAQ functions, you will either need to rewrite the program using NI-DAQmx, or make use of the Traditional NI-DAQ Compatibility VIs. For more information on these VIs, refer to the "Traditional NI-DAQ Compatibility VIs Version 1.3 for Windows 2000/NT/XP" driver update.
  • M Series devices use APFI 0 and APFI 1 for analog triggering rather than PFI 0, therefore the source of the trigger input in your application may have to be changed.
  • The DIO Port 0 on M Series devices can either be 8 or 32 lines. Therefore, a U8 port read or write that can be used on E Series devices may not work with all M Series devices. The function will return an error if the port actually contains 32 lines.
  • For multidevice synchronization, E Series devices make use of a master timebase from which all sample clocks are derived. M Series devices introduce a new concept for synchronization called a reference clock. This reference clock is essentially the source of the internal timebases that M Series boards use. To synchronize PCI M Series devices, one device should export its 10 MHz reference clock over RTSI to be used as the reference clock by other M Series devices in the acquisition. This will synchronize the timebases of all the boards. PXI M Series devices have the ability to phase lock their 10 MHz reference clocks to a common clock on the PXI backplane, thereby synchronizing the timebases of all the boards.