SMC-Based Digitizers Timing Diagram

SMC-Based digitizers (NI 5105/5114/5122/5124/5142/5152/5153/5154/5160/5162/5622/5922) support multirecord acquisitions, which allow the capture of multiple triggered waveforms without software intervention. In this mode, the digitizer automatically begins storing a new record to onboard memory a short time after finishing the previous record. The number of records and record size are both configurable.

The following timing diagram illustrates how SMC-based digitizers react to the user-configurable input triggers during a multirecord acquisition.

Each state prefixed by Wait for is a state in which an input trigger can be configured. This trigger tells the digitizer when to transition out of that particular state. The hardware is only sensitive to a particular trigger when in that trigger's appropriate Wait for state. For example, the hardware is not sensitive to a high level on the Advance Trigger until it enters the Wait for the Advance trigger state.

The exportable events are also shown in the timing diagram. The End of Record Event is generated once per record when the digitizer has acquired all of its pre- and post-Reference Trigger samples. This signal can be used for handshaking between devices in a system. The Done Event asserts when all of the records have been completed, but it does not assert if the acquisition is aborted or times out.