PIC18LF252-ISP Datasheet, PDF (277/332 Pages) Microchip Technology – High-Performance, Enhanced Flash Microcontrollers with 10-Bit A/D

PIC18FXX2
FIGURE 22-9:
TIMER0 AND TIMER1 EXTERNAL CLOCK TIMINGS
T0CKI
T1OSO/T1CKI
40
41
42
45
46
47
48
TMR0 or
TMR1
Note: Refer to Figure 22-4 for load conditions.
TABLE 22-8: TIMER0 AND TIMER1 EXTERNAL CLOCK REQUIREMENTS
Param
No.
Symbol
Characteristic
Min
Max Units Conditions
40
Tt0H
T0CKI High Pulse Width
No Prescaler
0.5TCY + 20
— ns
With Prescaler
10
— ns
41 Tt0L
T0CKI Low Pulse Width
No Prescaler
0.5TCY + 20
— ns
With Prescaler
10
— ns
42 Tt0P
T0CKI Period
No Prescaler
TCY + 10
— ns
With Prescaler
Greater of:
—
20 nS or TCY + 40
N
ns N = prescale
value
(1, 2, 4,..., 256)
45
Tt1H
T1CKI High
Synchronous, no prescaler
Time
Synchronous, PIC18FXXX
with prescaler _PIC18LFXXX
0.5TCY + 20
10
25
— ns
— ns
— ns
Asynchronous PIC18FXXX
30
— ns
PIC18LFXXX
50
— ns
46 Tt1L
T1CKI Low
Time
Synchronous, no prescaler
Synchronous,
with prescaler
PIC18FXXX
PIC18LFXXX
0.5TCY + 5
10
25
— ns
— ns
— ns
Asynchronous PIC18FXXX
30
— ns
PIC18LFXXX
50
— ns
47
Tt1P
T1CKI input Synchronous
period
Greater of:
—
20 nS or TCY + 40
N
ns N = prescale
value
(1, 2, 4, 8)
Asynchronous
60
— ns
Ft1
T1CKI oscillator input frequency range
DC
50 kHz
48 Tcke2tmrI Delay from external T1CKI clock edge to timer
increment
2 TOSC
7 TOSC —
© 2006 Microchip Technology Inc.
DS39564C-page 275