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FUJITSU F2MCTM-16LX User Manual

Page 104

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CHAPTER 4 DELAYED INTERRUPT GENERATION MODULE

4.4

Explanation of Operation of Delayed Interrupt Generation
Module

The delayed interrupt generation module has a function for generating or canceling an
interrupt request by software.

Explanation of Operation of Delayed Interrupt Generation Module

Using the delayed interrupt generation module requires the setting shown in Figure 4.4-1 .

Figure 4.4-1 Setting for Delayed Interrupt Generation Module

When the R0 bit in the delayed interrupt request generate/cancel register (DIRR) is set to "1" (DIRR: R0 =

1), an interrupt request is generated. There is no interrupt request enable bit.

Operation of delayed interrupt generation module

When the R0 bit in the delayed interrupt request generate/cancel register (DIRR) is set to "1", the

interrupt request latch is set to "1" and an interrupt request is generated to the interrupt controller.

An interrupt request is generated to the CPU when the interrupt controller prioritizes the interrupt

request over other requests.

When the interrupt level mask bit of the condition code register (CCR: ILM) is compared to the

interrupt request level (ICR: IL), and the interrupt request level is higher than ILM, CPU executes the

delayed interrupt processing after the instruction currently being executed is completed.

At interrupt processing, the user program sets the R0 bit to 0 to cancel the interrupt request and performs

task switching.

Figure 4.4-2 shows the operation of the delayed interrupt generation module.

Figure 4.4-2 Operation of Delayed Interrupt Generation Module

: Undefined bit

: Used bit

bit15

14

13

12

11

10

9

bit8

DIRR

R0

DIRR

ICR YY

ICR XX

CMP

IL

ILM

CMP

CPU

Delayed interrupt generation module

Other
request

Interrupt controller

Interrupt
processing