
22
μ
PD75216A
5.6
TIMER/PULSE GENERATOR
The
μ
PD75216A incorporates one channel of timer/pulse generator which can be used as a timer or a pulse
generator. The timer/pulse generator has the following functions.
(a)
Functions available in the timer mode
8-bit interval timer operation (IRQTPG generation) enabling the clock source to be varied at 5 levels
Square wave output to PPO pin
(b)
Functions available in the PWM pulse generation mode
14-bit accuracy PWM pulse output to the PPO pin (Used as a digital-to-analog converter and applicable
to tuning)
Fixed time interval ( 2
f
XX
If pulse output is not necessary, the PPO pin can be used as a 1-bit output port.
Note
If the STOP mode is set while the timer/pulse generator is in operation, miss-operation may result.
To prevent that from occurring, preset the timer/pulse generator to the stop state using its mode
register.
Fig. 5-5 Block Diagram of Timer/Pulse Generator (Timer Mode)
15
8
8
MODL
MODH
TPGM3
(Set to "1")
8
8
1/2
f
X
TPGM1
CP
TPGM4TPGM5 TPGM7
PPO
INTTPG
IRQTPG
Set Signal
Internal Bus
Modulo Register L (8)
Modulo Register H (8)
Modulo Latch H (8)
Comparator (8)
Clear
Prescalar Select Latch (5)
Clear
Frequency
Divider
Set
T F/F
Selector
Output Buffer
Match
Count Register (8)