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Rev. C - 15 January, 2001

TS80C31X2

6.4 Interrupt System

The TS80C31X2 has a total of 5 interrupt vectors: two external interrupts (INT0 and INT1), two timer interrupts

(timers 0 and 1) and the serial port interrupt. These interrupts are shown in Figure 7.

Figure 7. Interrupt Control System

Each of the interrupt sources can be individually enabled or disabled by setting or clearing a bit in the Interrupt

Enable register (See Table 8.). This register also contains a global disable bit, which must be cleared to disable

all interrupts at once.

Each interrupt source can also be individually programmed to one out of four priority levels by setting or clearing

a bit in the Interrupt Priority register (See Table 9.) and in the Interrupt Priority High register (See Table 10.).

shows the bit values and priority levels associated with each combination.

IE1

0

3

High priority

interrupt

Interrupt

polling

sequence, decreasing

from high to low priority

Low priority

interrupt

Global Disable

Individual Enable

TI

RI

TF0

INT0

INT1

TF1

IPH, IP

IE0

0

3

0

3

0

3

0

3