CHAPTER 7 8-BIT TIMER
7.1 8-Bit Timer Functions
An 8-bit timer (one channel, timer 50) and an 8-bit timer/event counter (one channel, timer 60) are incorporated in
the µPD789426, 789436, 799446, 789456 Subseries. The operation modes listed in the following table can be set
via mode register settings.
Table 7-1. Operation Modes
Channel
Timer 50
Timer 60
Available
Mode
8-bit timer counter mode
(Discrete mode)
Available
16-bit timer counter mode
(Cascade connection mode)
Available
Available
Carrier generator mode
PWM output mode
Available
Available
(Free-running mode) (Pulse generator mode)
(1) 8-bit timer counter mode (discrete mode)
The following functions can be used in this mode.
•
•
•
Interval timer with 8-bit resolution
External event counter with 8-bit resolution (timer 40 only)
Square wave output with 8-bit resolution
(2) 16-bit timer counter mode (cascade connection mode)
Operation as a 16-bit timer/event counter is enabled during cascade connection mode.
The following functions can be used in this mode.
•
•
•
Interval timer with 16-bit resolution
External event counter with 16-bit resolution
Square wave output with 16-bit resolution
(3) Carrier generator mode
The carrier clock generated by timer 60 is output in cycles set by timer 50.
(4) PWM output mode
(a) Timer 50: Free-running mode
The timer output status inverts repeatedly due to a match between TM50 and CR50 and TM50
overflow, and pulses of any duty ratio are output.
User’s Manual U15075EJ1V0UM00
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NEC [ NEC ]
