NEC PD78078 Manuale Utente

523

CHAPTER 22 INTERRUPT FUNCTIONS

22.5 Test Functions

In this function, when the watch timer overflows and when a rising edge of port 4 is detected, the corresponding

test input flag is set (1), and a standby release signal is generated.

Unlike the interrupt function, vectored processing is not performed.

There are two test input factors as shown in Table 22-5. The basic configuration is shown in Figure 22-18.

Table 22-5. Test Input Factors

Test Input Factors

Name

Trigger

INTWT

Clock timer overflow

Internal

INTPT4

Negative edge detection at port 4

External

Figure 22-18. Basic Configuration of Test Function

IF : Test input flag

MK: Test mask flag

22.5.1 Registers controlling the test function

The test function is controlled by the following three registers.

• Interrupt request flag register 1L (IF1L)

• Interrupt mask flag register 1L (MK1L)

• Key return mode register (KRM)

The names of the test input flag and test mask flag corresponding to the test input signals are listed in Table

22-6.

Table 22-6. Flags Corresponding to Test Input Signals

Test Input Signal Name

Test Input Flag

Test Mask Flag

INTWT

WTIF

WTMK

INTPT4

KRIF

KRMK

Internal/

external

Internal bus

Test input
signal

Standby
release signal