NEC PD78076Y Network Card User Manual


 
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CHAPTER 8 16-BIT TIMER/EVENT COUNTER
8.1 Outline of Timers Incorporated into
µ
PD78078, 78078Y Subseries
This chapter explains the 16-bit timer/event counter. First of all, the timers incorporated into the
µ
PD78078, 78078Y
Subseries and the related circuits are outlined below.
(1) 16-bit timer/event counter (TM0)
The TM0 can be used for an interval timer, PWM output, pulse widths measurement (infrared ray remote
control receive function), external event counter, square wave output of any frequency or one-shot pulse
output.
(2) 8-bit timers/event counters 1 and 2 (TM1 and TM2)
TM1 and TM2 can be used to serve as an interval timer and an external event counter and to output square
waves with any selected frequency. Two 8-bit timer/event counters can be used as one 16-bit timer/event
counter (See CHAPTER 9 8-BIT TIMER/EVENT COUNTERS 1 AND 2).
(3) 8-bit timer/event counters 5 and 6 (TM5 and TM6)
TM5 and TM6 can be used to serve as an interval timer and external event counter and to output any
frecuency square waves. These cannot be used as 16-bit timer/event counters (See CHAPTER 10 8-
BIT TIMER/EVENT COUNTER 5 AND 6).
(4) Watch timer (TM3)
This timer can set a flag every 0.5 sec. and simultaneously generates interrupt requests at the preset time
intervals (See CHAPTER 11 WATCH TIMER).
(5) Watchdog timer (WDTM)
WDTM can perform the watchdog timer function or generate non-maskable interrupt requests, maskable
interrupt requests and RESET at the preset time intervals (See CHAPTER 12 WATCHDOG TIMER).
(6) Clock output control circuit
This circuit supplies other devices with the divided main system clock and the subsystem clock (See CHAPTER
13 CLOCK OUTPUT CONTROL CIRCUIT).
(7) Buzzer output control circuit
This circuit outputs the buzzer frequency obtained by dividing the main system clock (See CHAPTER
14
BUZZER OUTPUT CONTROL CIRCUIT).