Advantech PCI-1752, Быстрый старт

Страница: 39 / 62

Chapter 4
– 32 – PCI-1752/54/56 User’s Manual
Advantech Co., Ltd.
www.advantech.com
Latch Port Data Function
The function enables you to latch the last data of each associated
digital input channels when the interrupt occurs and you can free the
latch function by clearing interrupt. We have organized every 16 bits
into one group. When the Latch Port Data Function is enabled for a
specific group, the values of all channel ports in this group will be
latched. The function is determined by the value in the
latch port data
disable/enable control bit in the interrupt control register, as shown in
Table 4-2.
Table 4-2 Latch port data disable/enable control bit
Interrupt Enable Control Function
The user can choose to enable or disable the interrupt function by
writing its corresponding value to the
interrupt disable/enable
control bit in the interrupt control register , as shown in Table 4-3.
Table 4-3 Interrupt disable/enable control bit values
Interrupt Triggering Edge Control
The interrupt can be triggered by a rising edge or a falling edge of the
interrupt signal, as determined by the value in the
interrupt triggering
edge control bit in the interrupt control register, as shown in Table 4-4.
Table 4-4 Interrupt triggering edge control bit values
Ln/E Latch port data when the interrupt occurs
0 Disable
1 Enable
INTn/E Interrupt control
0 Disable
1 Enable
En Triggering edge of interrupt signal
0 Falling edge trigger
1 Rising edge trigger