w83c553f Winbond Electronics Corp America, w83c553f Datasheet - Page 100

• Manufacturer Part Number: w83c553f
• Description: System I/o Controller With Pci Arbiter
• Manufacturer: Winbond Electronics Corp America

W83C553F
Initialization Command Word 2 Register
Function:
Type:
Bit Description:
WINBOND SYSTEMS LABORATORY
Bits [7:3]:
Bits [2:0]:
The Initialization Command Word 2 (ICW2) Register is used to initialize the interrupt controller with the
five most significant bits of the interrupt vector address. The value programmed into bits [7:3] is used by
the host CPU to define the base address in the interrupt vector table for the interrupt routines associated
with each IRQ on the controller.
Write Only
TA[7:3]. Interrupt Vector Base Address. These bits define the base address in the interrupt
vector table for the interrupt routines associated with each interrupt request level input. For
Interrupt Controller #1, a typical value is "00001;" for Interrupt Controller #2, a typical value is
"10000."
Reserved. Interrupt Request Level. When writing ICW2, these bits should all be "0." During
an interrupt acknowledge cycle, these bits are coded with a simple binary value determining
which IRQ is enable.
Electrical Specifications
97