PIC16C770 Microchip Technology Inc., PIC16C770 Datasheet - Page 50

• Manufacturer Part Number: PIC16C770
• Description: 18/20-pin, 8-bit Cmos Microcontrollers With 10/12-bit A/d
• Manufacturer: Microchip Technology Inc.

PIC16C717/770/771
6.1.1
In this mode, Timer1 is being incremented via an exter-
nal source. Increments occur on a rising edge. After
Timer1 is enabled in Counter mode, the module must
first have a falling edge before the counter begins to
increment.
FIGURE 6-1:
FIGURE 6-2:
DS41120B-page 48
Note 1: When the T1OSCEN bit is cleared, the inverter and feedback resistor are turned off. This eliminates power drain.
T1CKI
(Initially high)
T1CKI
(Initially low)
RB6/T1OSO/T1CKI/P1C
RB7/T1OSI/P1D
Note: Arrows indicate counter increments.
First falling edge
of the T1ON enabled
TIMER1 COUNTER OPERATION
TIMER1 INCREMENTING EDGE
TIMER1 BLOCK DIAGRAM
Set flag bit
TMR1IF on
Overflow
First falling edge
of the T1ON enabled
TMR1H
T1OSC
TMR1
TMR1L
Oscillator(1)
T1OSCEN
Enable
Clock
Fosc/4
Internal
TMR1ON
on/off
TMR1CS
1
0
T1CKPS<1:0>
T1SYNC
Prescaler
1, 2, 4, 8
0
1
2
2002 Microchip Technology Inc.
Synchronized
clock input
Synchronize
SLEEP input
det