7733 datasheet(624/940 Pages) RENESAS

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7733 Group User’s Manual

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APPENDIX

Interrupt

(1)

If the edge sense or level sense is selected, an external interrupt request occurs when the level

____

of an input signal on the INTi pin changes. This is independent of clock

φ1.

At this time, if the edge sense is selected, the interrupt request bit is set to “1,” also.

(2)

There are two methods: one is the method to use the external interrupt’s level sense; the other

one is the method to use the timer’s event counter mode.

Method to use the external interrupt’s level sense

As for hardware, input a logical sum of several interrupt signals (for example, ‘a’, ‘b’, and ‘c’)

____

to the INTi pin and input each signal to the corresponding port.

____

As for software, check the ports’ input levels in an INTi interrupt routine in order to detect a

signal (one of signals ‘a,’ ‘b,’ and ‘c’) which is input.

(1)

____

At what timing of clock

φ1 is an external interrupt (an input signal on the INTi pin) detected?

(2)

____

Suppose that more than three external interrupt input pins (INTi) are necessary, what should I do?

Method to use the timer’s event counter mode

As for hardware, input an interrupt signal to the TAiIN or TBiIN pin.

As for software, set the timer’s operating mode to the event counter mode and set value

“000016” to the timer. Furthermore, select a valid edge.

The timer’s interrupt request occurs when an interrupt signal (selected valid edge) is input.

Note : The same process can be realized by using the key input interrupt function, also.

M37733MHBXXXFP

Port

INTi

Appendix 9. Q & A

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