Overview Of 8-Bit Pwm Timer - Fujitsu F2MC-8L F202RA Hardware Manual

CHAPTER 7 8-BIT PWM TIMER
7.1

Overview of 8-bit PWM Timer

An 8-bit PWM timer has the interval timer functions and the PWM timer functions of an
8-bit resolution. A counter is incremented using interval timer functions in
synchronization with three types of internal count clocks or the output of 8/16-bit
capture timer/counter. The user can select one of these functions. Therefore, the 8-bit
interval timer can be set and the square wave of any frequency can be output using the
set output. In addition, if a low-pass filter is connected to the PWM output, the D/A
converter can be used.
■
Interval Timer Functions (Functions to Output the Square Wave)
Interrupts are generated repeatedly at any interval by the interval timer functions.
Because the output level of the pin (P50/PWM pin) can be inverted for each interrupt, the square wave of
any frequency can also be output.
• An interval timer operation from the cycle of the count clock to 2
• The count clock can be selected from four types.
Table 7.1-1 shows the range of intervals and square wave output.
Table 7.1-1 Range of Intervals and Square Wave Output
Count clock cycle
1
Internal count
2
clock
3
8/16-bit timer
4
count clock
t : Instruction cycle (Affected by the clock mode and others.)
INST
t : Output cycle of an 8/16-bit capture timer
EXT
136
Interval
1t
1t
INST
INST
16t 4
2 t
INST
INST
64t 6
2 t
INST
INST
2t
2t
INST
INST
32t 5
2 t
INST
INST
512t 9
2 t
INST
INST
1t
1t
EXT
EXT
8
to 2 t
INST
12
to 2 t
INST
14
to 2 t
INST
17
to 2 t
INST
21
to 2 t
INST
25
to 2 t
INST
16
to 2 t
EXT
8
-times cycle is possible.
Square wave output (Hz)
9
1/ (2t ) to 1/ (2 t
INST INST
5 13
1/ (2 t ) to 1/ (2 t
INST INST
7 15
1/ (2 t ) to 1/ (2 t
INST INST
2 10
1/ (2 t ) to 1/ (2 t
INST INST
6 14
1/ (2 t ) to 1/ (2 t
INST INST
10 18
1/ (2 t ) to 1/ (2 t
INST INST
9
1/ (2t ) to 1/ (2 t )
EXT EXT
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