The information in this topic applies to analog input modules with a master timebase.

Table 94. Analog Input Modules with a Master Timebase
  • NI 9202
  • NI 9218
  • NI 9225
  • NI 9227
  • NI 9229
  • NI 9230
  • NI 9231
  • NI 9232
  • NI 9234
  • NI 9235
  • NI 9236
  • NI 9237
  • NI 9238
  • NI 9239
  • NI 9242
  • NI 9244
  • NI 9246
  • NI 9247
  • NI 9250
  • NI 9251
  • NI 9252
  • NI 9253
  • NI 9770
  • NI 9775

The module input channels are sampled simultaneously at the data rate configured for the module. Use the Start and Stop channels to put the module in and out of acquisition mode.

A module that is in acquisition mode can only acquire data. When a module is in acquisition mode, you cannot perform other operations, such as:
  • You can not access module properties when a module is in acquisition mode.
  • You can not access TEDS information, if supported, when a module is in acquisition mode.
Use the FPGA I/O Node to read the data from the module.
Note  Create FPGA I/O items for the module before you can configure the items using the FPGA I/O Node.

Example

The module Getting Started (FPGA) VI at labview\examples\CompactRIO\Module Specific\<module>\<module> Getting Started shows how to read from a module.

Putting the Module in Acquisition Mode

Complete the following steps to put the module in acquisition mode.

  1. Configure an FPGA I/O Node with the Start channel of the module.
  2. Wire a Boolean constant set to TRUE to the Start input of the FPGA I/O Node.
    A synchronization pulse is sent to the module. The module starts acquiring data at the data rate you configure.

Reading Data from the Module

When the module starts acquiring data, you can use an FPGA I/O Node to read data from the module.

Connect the AI output of the FPGA I/O Node [1]1 For the NI 9770, connect the RF In/I or RF In/Q items. to various types of functions, including an FPGA Memory function or an FPGA FIFO function.

To ensure that the VI reads the data synchronously when reading multiple channels on the module, place the channels in the same FPGA I/O Node.

The module internally acquires data at a specified rate. The FPGA I/O Node does not return data until new data has been acquired by the module.

Note If the module did not start acquiring data or stops acquiring data while an FPGA I/O Node is waiting for data from the module, the FPGA I/O Node returns I/O Not Start error 65582.

Exiting Acquisition Mode

Complete the following steps to exit acquisition mode.

  1. Configure an FPGA I/O Node with the Stop channel of the module.
  2. Write a TRUE to the Stop input.
    The module is no longer in acquisition mode. You can now access its properties or, for some modules, TEDS information.

1 For the NI 9770, connect the RF In/I or RF In/Q items.