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5. Digital Output (DO)
This chapter introduces the digital signal output for the USB-3200 series data acquisition
device
. The digital input is referred to as DO here, the abbreviation of Digital Output. Figure
5.1 is a schematic diagram of the digital output circuit.
Figure 5.1 Digital output circuit
5.1.
Signal output mode
When the USB-3200 series data acquisition
device
is utilized for digital output, the following
four output modes are supported:
Immediate output
Finite number output
Infinite number of loop output
Infinite non-loop output
Immediate output
Immediate output refers to the output state without buffer and no waveform. The computer sends
a command to the acquisition
device
, and it immediately outputs the specified level state.
Hardware timing
The three output modes mentioned below refer to the mode of outputting digital waveforms, so
the sampling rate of the output waveform is an important parameter. When the acquisition
device
is in DO mode, the DO sampling clock is generated by hardware timing. The sampling clock
signal can be generated internally or externally.
For details on using an externally supplied sampling clock, refer to the "Synchronization System"
chapter.
Finite number output mode
The limited number of output modes means that the digital waveform data to be output is first
stored in the hardware FIFO, then the output sampling rate is set, the number of times the