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PIC18F2682 Datasheet, PDF (441/484 Pages) Microchip Technology – 28/40/44-Pin Enhanced Flash Microcontrollers with ECAN Technology, 10-Bit A/D and nanoWatt Technology | |||
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PIC18F2682/2685/4682/4685
FIGURE 27-9:
TIMER0 AND TIMER1 EXTERNAL CLOCK TIMINGS
T0CKI
T1OSO/T13CKI
40
41
42
45
46
TMR0 or
TMR1
47
48
Note: Refer to Figure 27-4 for load conditions.
TABLE 27-11: TIMER0 AND TIMER1 EXTERNAL CLOCK REQUIREMENTS
Param
No.
Sym
Characteristic
Min
Max Units Conditions
40 TT0H
T0CKI High Pulse Width
No prescaler 0.5 TCY + 20 â ns
With prescaler
10
â ns
41 TT0L
T0CKI Low Pulse Width
No prescaler 0.5 TCY + 20 â ns
With prescaler
10
â ns
42 TT0P
T0CKI Period
No prescaler
TCY + 10
â ns
With prescaler Greater of: â
20 ns or
(TCY + 40)/N
ns N = prescale value
(1, 2, 4,..., 256)
45 TT1H
T13CKI High Synchronous, no prescaler
0.5 TCY + 20 â
Time
Synchronous, PIC18FXXXX
10
â
with prescaler PIC18LFXXXX
25
â
ns
ns
ns VDD = 2.0V
Asynchronous PIC18FXXXX
30
â ns
PIC18LFXXXX
50
â
ns VDD = 2.0V
46 TT1L
T13CKI Low Synchronous, no prescaler
0.5 TCY + 5
â
ns
Time
Synchronous, PIC18FXXXX
10
â ns
with prescaler PIC18LFXXXX
25
â
ns VDD = 2.0V
Asynchronous PIC18FXXXX
30
â ns
PIC18LFXXXX
50
â
ns VDD = 2.0V
47 TT1P
T13CKI Input Synchronous
Period
Greater of: â
20 ns or
(TCY + 40)/N
ns N = prescale value
(1, 2, 4, 8)
Asynchronous
60
â ns
FT1
T13CKI Oscillator Input Frequency Range
DC
50 kHz
48 TCKE2TMRI Delay from External T13CKI Clock Edge to
Timer Increment
2 TOSC
7 TOSC â
© 2007 Microchip Technology Inc.
Preliminary
DS39761B-page 439
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