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Power Supply
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3. Digital Output
（
DO
）
This chapter introduces the digital signal output for the PCI-1232 data acquisition device. The digital
input is referred to as DO here, the abbreviation of Digital Output.
3.1
Schematic diagram of digital output circuit
The circuit diagram of digital output is shown in Figure 3.1.
COM
DO
ISOGND
Figure 3.1 Schematic diagram of digital output circuit
3.2
Signal output mode
PCI-1232 data acquisition device supports the following three output modes for digital
output:
Immediate output
Finite length waveform output
Infinite loop waveform output
The sampling rate of the latter two modes adopts hardware timing.
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
Hardware timing means that the sampling rate of DO output is controlled by hardware
digital signal (DO sampling clock), which is generated internally by the acquisition device.
5V
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Load
