PIC16F87 Datasheet, PDF (182/214 Pages) Microchip Technology – 18/20/28-Pin Enhanced FLASH Microcontrollers with nanoWatt Technology

PIC16F87/88
FIGURE 18-8:
TIMER0 AND TIMER1 EXTERNAL CLOCK TIMINGS
RA4/T0CKI
40
41
42
RB6/T1OSO/T1CKI
TMR0 or TMR1
45
46
47
48
Note: Refer to Figure 18-3 for load conditions.
TABLE 18-6: TIMER0 AND TIMER1 EXTERNAL CLOCK REQUIREMENTS
Param
No.
Symbol
Characteristic
Min
Typ† Max Units
Conditions
40* Tt0H
T0CKI High Pulse Width
No Prescaler 0.5 TCY + 20 — — ns Must also meet
With Prescaler
10
—
—
ns ^{parameter 42}
41* Tt0L
T0CKI Low Pulse Width
No Prescaler 0.5 TCY + 20 — — ns Must also meet
With Prescaler
10
—
—
ns ^{parameter 42}
42* Tt0P
T0CKI Period
No Prescaler
TCY + 40
— — ns
With Prescaler Greater of: — — ns N = prescale value
20 or TCY + 40
(2, 4, ..., 256)
N
45* Tt1H
T1CKI High Synchronous, Prescaler = 1
0.5 TCY + 20 — — ns Must also meet
Time
Synchronous, PIC16F87/88
15
—
—
ns ^{parameter 47}
Prescaler = 2,4,8 _PIC16LF87/88
25
— — ns
Asynchronous PIC16F87/88
30
— — ns
PIC16LF87/88
50
— — ns
46* Tt1L
T1CKI Low Synchronous, Prescaler = 1
0.5 TCY + 20 — — ns Must also meet
Time
Synchronous, PIC16F87/88
15
—
—
ns ^{parameter 47}
Prescaler = 2,4,8 _PIC16LF87/88
25
— — ns
Asynchronous PIC16F87/88
30
— — ns
PIC16LF87/88
50
— — ns
47* Tt1P
T1CKI Input Synchronous
Period
PIC16F87/88 Greater of: — — ns N = prescale value
30 or TCY + 40
(1, 2, 4, 8)
N
PIC16LF87/88 Greater of:
50 or TCY + 40
N
N = prescale value
(1, 2, 4, 8)
Asynchronous PIC16F87/88
60
— — ns
PIC16LF87/88
100
— — ns
Ft1
Timer1 Oscillator Input Frequency Range
(Oscillator enabled by setting bit T1OSCEN)
DC
— 32.768 kHz
48 TCKEZtmr1 Delay from External Clock Edge to Timer Increment 2 TOSC
— 7 TOSC —
* These parameters are characterized but not tested.
† Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are
not tested.
DS30487B-page 180
Preliminary
 2003 Microchip Technology Inc.