beautypg.com

4 interrupt vector generation and calculation, Interrupt vector generation and calculation -14, Interrupt request masking -14 – Motorola MPC8260 User Manual

Page 152: Encoding the interrupt vector -14

background image

4-14

MPC8260 PowerQUICC II UserÕs Manual

MOTOROLA

Part II. ConÞguration and Reset

Figure 4-9. Interrupt Request Masking

4.2.4 Interrupt Vector Generation and Calculation

Pending unmasked interrupts are presented to the core in order of priority. The interrupt
vector that allows the core to locate the interrupt service routine is made available to the
core by reading SIVEC. The interrupt controller passes an interrupt vector corresponding
to the highest-priority, unmasked, pending interrupt. Table 4-3 lists encodings for the six
low-order bits of the interrupt vector.

Table 4-3. Encoding the Interrupt Vector

Interrupt Number

Interrupt Source Description

Interrupt Vector

0

Error (No interrupt)

0b00_0000

1

I

2

C

0b00_0001

2

SPI

0b00_0010

3

RISC Timers

0b00_0011

4

SMC1

0b00_0100

5

SMC2

0b00_0101

SCCE

SCCM

13 Input (or

SIPNR

Mask

Bit

SIMR

(Other Unmasked Requests)

Request to
the core

Mask

Bit

Event

Bit

13 Event Bits)