
7540 Group User’s Manual
APPLICATION
2-31
2.2 Timer A
Fig. 2.2.22 Setting method for pulse width HL continuously measurement mode (2)
b7
b0
1
b7b0
1
b7b0
0
b7b0
0
b7
b0
0
11
b7
b0
1
Process 7: In order not to execute the no requested interrupt processing, set “0” (no requested)
to the timer A interrupt request bit and CNTR1 interrupt request bit (Note).
Interrupt request register 1 (IREQ1) [Address 3C16]
Process 8: When the interrupt is used, set “1” (interrupt enabled) to the timer A
interrupt enable bit or CNTR1 interrupt enable bit.
No CNTR1 interrupt request issued
Interrupt control register 2 (ICON2) [Address 3F16]
Timer A interrupt enabled
Timer A mode register (TAM) [Address 1D16]
Timer A count start
Process 9: Start counting of timer A.
Interrupt request register 2 (IREQ2) [Address 3D16]
No timer A interrupt request issued
Interrupt control register 1 (ICON1) [Address 3E16]
CNTR1 interrupt enabled
Interrupt edge selection register (INTEDGE) [Address 3A16]
Key-on wakeup disabled
Process 6: In order to use the CNTR1 pin function of the P00/CNTR1 pin, disable the P00 key-on wakeup function.
Note: In the pulse width HL continuously measurement mode, the CNTR1 interrupt request occurs
at the rising edge and falling edge of the P00/CNTR1 pin regardless of the value of the
P00/CNTR1 active edge switch bit of the timer A mode register.