DSPIC33FJ32GS608 datasheet(123/416 Pages) MICROCHIP

123 / 416 page

 2009 Microchip Technology Inc.

Preliminary

DS70591B-page 123

dsPIC33FJ32GS406/606/608/610 and dsPIC33FJ64GS406/606/608/610

7.0

INTERRUPT CONTROLLER

The

dsPIC33FJ32GS406/606/608/610

and

dsPIC33FJ64GS406/606/608/610 interrupt controller

reduces the numerous peripheral interrupt request

signals to a single interrupt request signal to the

dsPIC33FJ32GS406/606/608/610

and

dsPIC33FJ64GS406/606/608/610 CPU. It has the

following features:

• Up to eight processor exceptions and software

traps

• Seven user-selectable priority levels

• Interrupt Vector Table (IVT) with up to 118 vectors

• A unique vector for each interrupt or exception

source

• Fixed priority within a specified user priority level

• Alternate Interrupt Vector Table (AIVT) for debug

support

• Fixed interrupt entry and return latencies

7.1

Interrupt Vector Table

The Interrupt Vector Table (IVT) is shown in Figure 7-1.

The IVT resides in program memory, starting at location

000004h. The IVT contains 126 vectors, consisting of

eight nonmaskable trap vectors, plus up to 118 sources

of interrupt. In general, each interrupt source has its own

vector. Each interrupt vector contains a 24-bit-wide

address. The value programmed into each interrupt

vector location is the starting address of the associated

Interrupt Service Routine (ISR).

Interrupt vectors are prioritized in terms of their natural

priority. This priority is linked to their position in the

vector table. Lower addresses generally have a higher

natural priority. For example, the interrupt associated

with vector 0 will take priority over interrupts at any

other vector address.

The

dsPIC33FJ32GS406/606/608/610

and

dsPIC33FJ64GS406/606/608/610 devices implement up

to 71 unique interrupts and five non-maskable traps.

These are summarized in Table 7-1.

7.1.1

ALTERNATE INTERRUPT VECTOR

TABLE

The Alternate Interrupt Vector Table (AIVT) is located

after the IVT, as shown in Figure 7-1. Access to the

AIVT is provided by the ALTIVT control bit

(INTCON2<15>). If the ALTIVT bit is set, all interrupt

and exception processes use the alternate vectors

instead of the default vectors. The alternate vectors are

organized in the same manner as the default vectors.

The AIVT supports debugging by providing a means to

switch between an application and a support

environment without requiring the interrupt vectors to

be reprogrammed. This feature also enables switching

between applications for evaluation of different

software algorithms at run time. If the AIVT is not

needed, the AIVT should be programmed with the

same addresses used in the IVT.

7.2

Reset Sequence

A device Reset is not a true exception because the

interrupt controller is not involved in the Reset process.

The

dsPIC33FJ32GS406/606/608/610

and

dsPIC33FJ64GS406/606/608/610 device clears its

registers in response to a Reset, which forces the PC to

zero. The digital signal controller then begins program

execution at location 0x000000. A GOTO instruction at the

Reset address can redirect program execution to the

appropriate start-up routine.

Note 1: This data sheet summarizes the features

of the dsPIC33FJ32GS406/606/608/610

and

dsPIC33FJ64GS406/606/608/610

families of devices. It is not intended to be

a comprehensive reference source. To

complement the information in this data

sheet, refer to Section 47. “Interrupts

(Part V)” (DS70597) in the “dsPIC33F/

PIC24H Family Reference Manual”,

which is available from the Microchip web

site (www.microchip.com).

2: Some registers and associated bits

described in this section may not be avail-

able on all devices. Refer to Section 4.0

“Memory Organization” in this data

sheet for device-specific register and bit

information.

Note:

Any unimplemented or unused vector

locations in the IVT and AIVT should be

programmed with the address of a default

interrupt handler routine that contains a

RESET instruction.

dsPIC33FJ32GS608 Datasheet(PDF) 123 Page - Microchip Technology

dsPIC33FJ32GS608 Datasheet(HTML) 123 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL