Technical Information 1-9
The system board's four SIMM sockets are assigned as banks A and B. Each SIMM kit
is inserted into a pair of sockets or bank. Bank A consist of sockets J28 and J27, and in
the desktop version can only accommodate low profile (1-, 2-, and 4-MB) SIMM sticks.
Bank B consist of sockets J25 and J26. Different size SIMMs cannot be intermixed
within a bank. See Section 3, Options, for installation instructions and SIMM memory con-
figurations.
Interrupt Controller
The interrupt controller operates as an interrupt manager for the entire AT system environ-
ment. The controller accepts requests from peripherals, issues interrupt requests to the
processor, resolves interrupt priorities, and provides vectors for the processor to determine
which interrupt routine to execute. The interrupt controller has priority assignment modes
that can be reconfigured at any time during system operations.
The interrupt levels are listed in Table Section 1-7. Interrupt-level assignments 0 through 15
are in order of decreasing priority. See Section 2, Setup and Configuration, for information
on changing the interrupts using Setup.
Table Section 1-7 Interrupt Level Assignments
Interrupt Priority Interrupt Device
IRQ00 Counter/Timer
IRQ01 Keyboard
IRQ02 Cascade (INT output from slave)
IRQ03 COM2*
IRQ04 COM1*
IRQ05 Parallel Port 2
IRQ06 Diskette Drive Controller*
IRQ07 Parallel Port 1*
IRQ08 Real-time clock
IRQ09 Available
IRQ10 Available
IRQ11 Available
IRQ12 PS/2 mouse*
IRQ13 Coprocessor
IRQ14 Primary IDE (fast)
IRQ15 Secondary IDE (standard)
*Industry standard locations
To Next Page
Loading...
