Table 6-3: Change-Of-State-Interrupt-Enable Register - ICS Advent PCI-DIO48 Series Product Manual

PCI-DIO48(S)(S) Manual
Change-of-State Interrupts
At Power-up or Reset, a latch disables all IRQ sources on the card. In order to properly
disable/enable interrupts, you must program the Change-Of-State Interrupt Enable Register first.
To program this Change-of-State-Interrupt-Enable Register, write to it at Base Address+B. Data
bits D0 through D5 control ports A, B, and C of the 8255 PPIs as shown in Table 4. Any access
of Base+B will enable the non-COS IRQ associated with
port C bit 3.
Writing a "one" disables the port; writing a "zero" enables it. When IRQs occur the interrupt state
is latched. To clear the latch, write anything to Base Address+F.
Page 6-6
Bit
D0
D1
D2
D3
D4
D5

Table 6-3: Change-of-state-interrupt-enable Register

Port Controlled
Group 0, Port A
Group 0, Port B
Group 0, Port C
Group 1, Port A
Group 1, Port B
Group 1, Port C
Manual 00650-529-1