NEC PD78F9488 - Manual (Page 120)

120
User’s Manual U15331EJ4V1UD
CHAPTER 7 8-BIT TIMERS 50, 60, AND 61
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
the µPD789489 Subseries. The operation modes listed in the following table can be set via mode register settings.
Table 7-1. Operation Modes
Channel
Mode
Timer 50 Timer 60 Timer 61
8-bit timer counter mode
(stand-alone mode) Available Available Available
16-bit timer counter mode
(cascade connection mode) Available Not available
Carrier generator mode Available Not available
PWM output mode Available Not available Not available
PPG output mode Not available Available Available
24-bit event counter mode
(connect with 16-bit timer 20) Not available Not available Available
(1) Mode to use 8-bit timer/event counter as discrete unit (stand-alone mode)
The following functions can be used in this mode.
• Interval timer with 8-bit resolution
• Square wave output with 8-bit resolution
• 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).