Fujitsu F2MC-8L F202RA Hardware Manual page 180

CHAPTER 8 8/16-BIT CAPTURE TIMER/COUNTER
Table 8.1-3 Interval Time and Square Wave Output Range in 16-bit Mode
Count clock cycle
Internal count clock
External clock
t : Instruction cycle (this cycle is affected by the clock mode, etc.)
INST
t : External clock cycle (1t
EXT
Note:
Example of calculating interval time and square wave frequency
If the oscillation (F
and the count clock cycle is set to 2t
square wave frequency output from the TO pin when the interval timer function is operated
continuously without modifying the TDR0 register value are calculated from the following expressions:
However, the values calculated from these expressions are valid when the highest speed clock of the
normal mode (CS1, CS0 = 11
control register (SYCC).
164
Interval time
2t
2t
INST
INST
2
4t
2 t
INST
INST
4
16t
2 t
INST
INST
6
64t
2 t
INST
INST
7
128t
2 t
INST
INST
8
256t
2 t
INST
INST
9
512t
2 t
INST
INST
1t
1t
EXT
EXT
greater than or equal to 4t
EXT
) is set to 12.5 MHz, the timer 0 data register (TDR0) value is set to DD
CH
, 1 instruction cycle = 4/F
B
Interval time = (2 × 4/F
CH
= (8/12.5 MHz) × (221 + 1)
142.1 µs
Output frequency = F
CH
= 12.5 MHz/(16 × (221 + 1))
3.53 kHz
17
to 2 t
INST
18
to 2 t
INST
20
to 2 t
INST
22
to 2 t
INST
23
to 2 t
INST
24
to 2 t
INST
25
to 2 t
INST
16
to 2 t
EXT
)
INST
8-bit mode operation, the interval time of timer 0 and the
INST
CH
) × (TDR0#1 register value + 1)
/(2 × 8 × (TDR0#1 register value + 1))
Square wave output range (Hz)
2 18
1/ (2 t ) to 1/ (2 t
INST INST
3 19
1/ (2 t ) to 1/ (2 t
INST INST
5 21
1/ (2 t ) to 1/ (2 t
INST INST
7 23
1/ (2 t ) to 1/ (2 t
INST INST
8 24
1/ (2 t ) to 1/ (2 t
INST INST
9 25
1/ (2 t ) to 1/ (2 t
INST INST
10 26
1/ (2 t ) to 1/ (2 t
INST
17
1/ (2t ) to 1/ (2 t
EXT EXT
) is selected according to the system clock
)
)
)
)
)
)
)
INST
)
(221),
H