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3.
Digital Input
（
DI
）
This chapter introduces the related contents of PCI-1132 data acquisition device used for
digital signal input.DI is the abbreviation of Digital Input here.
The circuit diagram of digital input is shown in Figure 3.1.
DI
ISOGND
Figure 3.1, digital input circuit Figure
3.1.
Digital sensitivity
The setting of digital input sensitivity is to filter the input level jitter of unpredictable
length, such as the jitter caused by button switch. Sensitivity is set in time units. For
example, the default value of digital input sensitivity of PCI-1132 is 20ms, and its
function mode is shown in Figure 3.2 below.
Actual input
Acquisition result
Figure 3.2 Schematic diagram of function mode of digital sensitivity
Take the default value of 20ms as an example. When PCI-1132 detects that the level of the
actual input port changes, it starts timing. When it reaches 20ms, it takes the current level
state of the actual input port as the acquisition result.
5V
ISOGND
20ms
20ms
