CP3BT26

10.4MASKABLE 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

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

 

 

 

 

IRQ Number

Description

 

 

 

 

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

 

 

All reserved interrupt vectors should point to default or error interrupt handlers.

10.5NESTED 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.

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National CP3BT26 Maskable Interrupt Sources, Nested Interrupts, Maskable Interrupts Assignment IRQ Number Description