Chapter 7 8-Bit Timers 50, 60, And 61; Functions Of 8-Bit Timers 50, 60, And 61; Operation Modes - NEC PD789488 User Manual

7.1 Functions of 8-Bit Timers 50, 60, and 61

One 8-bit timer channel (timer 50) and two 8-bit timer/event counter channels (timer 60 and 61) are incorporated in
µ
the PD789489 Subseries. The operation modes listed in the following table can be set via mode register settings.
Mode
8-bit timer counter mode
(stand-alone mode)
16-bit timer counter mode
(cascade connection mode)
Carrier generator mode
PWM output mode
PPG output mode
24-bit event counter mode
(connect with 16-bit timer 20)
(1) Mode to use 8-bit timer/event counter as discrete unit (stand-alone mode)
The following functions can be used in this mode.
<Timer 50>
• Interval timer with 8-bit resolution
• Square wave output with 8-bit resolution
<Timer 60 and 61>
• Interval timer with 8-bit resolution
• External event counter with 8-bit resolution
• Square wave output with 8-bit resolution
(2) Mode to use timer 50 and timer 60 connected in cascade (16-bit resolution: cascade connection)
Operation as a 16-bit timer/event counter is enabled in 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 the cycle set by timer 50.
(4) PWM output mode (PWM: Pulse Width Modulator)
Pulses are output using any duty ratio (pulse width). The cycle (overflow cycle of the timer) becomes
constant (free running).
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CHAPTER 7 8-BIT TIMERS 50, 60, AND 61

Table 7-1. Operation Modes
Channel Timer 50
Available
Available
Not available
Not available
User's Manual U15331EJ4V1UD
Timer 60
Available
Available
Available
Not available
Available
Not available
Timer 61
Available
Not available
Not available
Not available
Available
Available