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CP3BT26
10.4
MASKABLE INTERRUPT SOURCES
Table 20 shows the interrupts assigned to various on-chip
maskable interrupts. The priority of simultaneous maskable
interrupts is linear, with IRQ47 having the highest priority.
Table 20
Maskable Interrupts Assignment
All reserved interrupt vectors should point to default or error
interrupt handlers.
10.5
NESTED INTERRUPTS
Nested NMI interrupts are always enabled. Nested
maskable interrupts are disabled by default, however an in-
terrupt handler can allow nested maskable interrupts by set-
ting the I bit in the PSR. The LPR instruction is used to set
the I bit.
Nesting of specific maskable interrupts can be allowed by
disabling interrupts from sources for which nesting is not al-
lowed, before setting the I bit. Individual maskable interrupt
sources can be disabled using the IENAM0 and IENAM1
registers.
Any number of levels of nested interrupts are allowed, limit-
ed only by the available memory for the interrupt stack.
IRQ Number
Description
IRQ47
TWM (Timer 0)
IRQ46
Bluetooth LLC 0
IRQ45
Bluetooth LLC 1
IRQ44
Bluetooth LLC 2
IRQ43
Bluetooth LLC 3
IRQ42
Bluetooth LLC 4
IRQ41
Bluetooth LLC 5
IRQ40
USB Interface
IRQ39
DMA Channel 0
IRQ38
DMA Channel 1
IRQ37
DMA Channel 2
IRQ36
DMA Channel 3
IRQ35
CAN
IRQ34
Advanced Audio Interface (AAI)
IRQ33
UART0 RX
IRQ32
CVSD/PCM Converter
IRQ31
ACCESS.bus
IRQ30
TA (Timer input A)
IRQ29
TB (Timer input B)
IRQ28
VTUA (VTU Interrupt Request 1)
IRQ27
VTUB (VTU Interrupt Request 2)
IRQ26
VTUC (VTU Interrupt Request 3)
IRQ25
VTUD (VTU Interrupt Request 4)
IRQ24
Microwire/SPI RX/TX
IRQ23
UART0 TX
IRQ22
UART0 CTS
IRQ21
Reserved
IRQ20
UART1 RX
IRQ19
UART1 TX
IRQ18
UART2 RX
IRQ17
UART2 TX
IRQ16
UART3 RX
IRQ15
UART3 TX
IRQ14
Reserved
IRQ13
ADC (Done)
IRQ12
MIWU Interrupt 0
IRQ11
MIWU Interrupt 1
IRQ10
MIWU Interrupt 2
IRQ9
MIWU Interrupt 3
IRQ8
MIWU Interrupt 4
IRQ7
MIWU Interrupt 5
IRQ6
MIWU Interrupt 6
IRQ5
MIWU Interrupt 7
IRQ4
Reserved
IRQ3
Random Number Generator (RNG)
IRQ2
Reserved
IRQ1
Flash Program/Data Memory
IRQ0
Reserved
IRQ Number
Description