NEC mPD789101, User Manual

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User’s Manual U13045EJ2V0UM00
103
CHAPTER 8 16-BIT TIMER COUNTER
The
µ
PD789134 Subseries features the following on-chip timers.
(1) 16-bit timer counter 20 (TM20)
The 16-bit timer counter references the free running counter and provides the functions such as timer interrupt
and timer output. In addition, the count value can be captured by a trigger pin.
(2) 8-bit timer/event counter 80 (TM80)
The 8-bit timer/event counter can be used as an interval timer, external event counter, and for square wave
output and PWM output of arbitrary frequency (see CHAPTER 9 8-BIT TIMER/EVENT COUNTER).
(3) Watchdog timer (WDTM)
The watchdog timer can generate non-maskable interrupts, maskable interrupts and RESET with arbitrary
preset intervals (see CHAPTER 10 WATCHDOG TIMER).
Table 8-1. Operation of Timer
16-Bit Timer Counter 20 8-Bit Timer/Event Counter 80 Watchdog Timer
Operating Interval timer — 1 channel 1 channel
Note
Mode
External event timer — 1 channel —
Function Timer output 1 output 1 output —
PWM output — 1 output —
Square wave output — 1 output —
Capture 1 input — —
Interrupt source 1 1 1
Note Since the watchdog timer provides the watchdog timer function and interval timer function, select the one
out of two functions.