CX82100 Home Network Processor Data Sheet
11
Interrupt Controller Interface Description
All peripheral interrupt sources are routed through the Interrupt Controller (INTC) and
reduced to one of two active low inputs to the ARM940T processor, fast interrupt (FIQ#)
or regular interrupt (IRQ#), as selected in the Interrupt Level Assignment Register
(INT_LA). No hardware-assisted priority scheme is implemented in the HNP other than
FIQ# having a higher priority than IRQ#. The system software must implement the
priority scheme for individual interrupts in the FIQ# and IRQ# exception handlers.
11.1
INTC Register Memory Map
INTC registers are identified in Table 11-1.
Table 11-1. INTC Registers
Register Label
INT_LA
INT_Stat
INT_SetStat
INT_Msk
INT_Mstat
Register Name
Interrupt Level Assignment Register
Interrupt Status Register
Interrupt Set Status Register
Interrupt Mask Register
ASB Address
0x00350040
0x00350044
0x00350048
0x0035004C
0x00350090
Type
RW
RR
WO
RW
RO
Default Value
0x00000000
0x00000000
0x00000000
0x00000000
0x00000000
Ref.
11.2.1
11.2.2
11.2.3
11.2.4
11.2.5
Interrupt Mask Status Register
11.2
INTC Registers
11.2.1
Interrupt Level Assignment Register (INT_LA: 0x00350040)
The INTC receives an interrupt signal from a potential interrupt source and compares it
with the corresponding interrupt level assignment register (INT_LA) to determine if a
fast interrupt (FIQ#) signal or a regular interrupt (IRQ#) signal should be sent to the
ARM940T processor. Setting the interrupt's corresponding bit on the Interrupt Level
Assignment Register to a 1 will cause a FIQ# interrupt, while a 0 will cause an IRQ#
interrupt.
Bit
31:0
Type
RW
Default
32’h00000000
Name
Int_LA_x
Description
Level Assignment Interrupt Control.
0 = The corresponding bit location in the INT_Stat register will cause
an IRQ# interrupt to the INTC if the interrupt has been enabled.
1 = The corresponding bit location in the INT_Stat register will cause
a FIQ# interrupt to the INTC if the interrupt has been enabled.
101306C
Conexant Proprietary and Confidential Information
11-1
CONEXANT [ CONEXANT SYSTEMS, INC ]
