© National Instruments | 3-13Analog OutputTo generate analog output, insert an analog output C Series module in any slot on the cDAQchassis. The generation specifications, such as the number of channels, channel configuration,update rate, and output range, are determined by the type of C Series module used. For moreinformation, refer to the documentation included with your C Series module(s).On a single analog output C Series module, you can assign any number of channels to either ahardware-timed task or a software-timed (single-point) task. However, you cannot assign somechannels to a hardware-timed task and other channels (on the same module) to a software-timedtask.(cDAQ-9184/9188) Any hardware-timed task or software-timed task can have channels frommultiple modules in the same chassis.Analog Output Data Generation MethodsWhen performing an analog output operation, you either can perform software-timed orhardware-timed generations. Hardware-timed generations must be buffered.Software-Timed GenerationsWith a software-timed generation, software controls the rate at which data is generated. Softwaresends a separate command to the hardware to initiate each DAC conversion. In NI-DAQmx,software-timed generations are referred to as on-demand timing. Software-timed generations arealso referred to as immediate or static operations. They are typically used for writing out a singlevalue, such as a constant DC voltage.The following considerations apply to software-timed generations:• If any AO channel on a module is used in a hardware-timed (waveform) task, no channelson that module can be used in a software-timed task• You can configure software-timed generations to simultaneously update• Only one simultaneous update task can run at a time• A hardware-timed AO task and a simultaneous update AO task cannot run at the same time
