PIC16C765 Microchip Technology Inc., PIC16C765 Datasheet - Page 45

• Manufacturer Part Number: PIC16C765
• Description: 8-bit Cmos Microcontrollers With Usb
• Manufacturer: Microchip Technology Inc.

7.0
The Timer1 module is a 16-bit timer/counter consisting
of two 8-bit registers (TMR1H and TMR1L), which are
readable and writable. The TMR1 Register pair
(TMR1H:TMR1L) increments from 0000h to FFFFh
and rolls over to 0000h. The TMR1 interrupt, if enabled,
is generated on overflow, which is latched in interrupt
flag bit TMR1IF (PIR1<0>). This interrupt can be
enabled/disabled by setting/clearing TMR1 interrupt
enable bit TMR1IE (PIE1<0>).
Timer1 can operate in one of two modes:
• As a timer
• As a counter
The operating mode is determined by the clock select
bit, TMR1CS (T1CON<1>).
REGISTER 7-1: TIMER1 CONTROL REGISTER (T1CON: 10h)
2000 Microchip Technology Inc.
bit7
bit 7-6: Unimplemented: Read as '0'
bit 5-4: T1CKPS<1:0>: Timer1 Input Clock Prescale Select bits
bit 3:
bit 2:
bit 1:
bit 0:
Note 1: On the rising edge after the first falling edge.
U-0
—
TIMER1 MODULE
11 = 1:8 Prescale value
10 = 1:4 Prescale value
01 = 1:2 Prescale value
00 = 1:1 Prescale value
T1OSCEN: Timer1 Oscillator Enable Control bit
1 = Oscillator is enabled
0 = Oscillator is shut off (The oscillator inverter is turned off to eliminate power drain)
T1SYNC: Timer1 External Clock Input Synchronization Control bit
TMR1CS = 1
1 = Do not synchronize external clock input
0 = Synchronize external clock input
TMR1CS = 0
This bit is ignored. Timer1 uses the internal clock when TMR1CS = 0.
TMR1CS: Timer1 Clock Source Select bit
1 = External clock from pin RC0/T1OSO/T1CKI
0 = Internal clock (F
TMR1ON: Timer1 On bit
1 = Enables Timer1
0 = Stops Timer1
U-0
—
T1CKPS1 T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON
R/W-0
INT
R/W-0
)
R/W-0
Preliminary
R/W-0
(1)
or RC1/T1OSI/CCP2
In timer mode, Timer1 increments every instruction
cycle. In counter mode, it increments on every rising
edge of the external clock input.
Timer1 can be enabled/disabled by setting/clearing
control bit TMR1ON (T1CON<0>).
Timer1 also has an internal “RESET input”. This
RESET can be generated by either of the two CCP
modules (Section 9.0). Register 7-1 shows the Timer1
control register.
When the Timer1 oscillator is enabled (T1OSCEN is
set), the RC1/T1OSI/CCP2 and RC0/T1OSO/T1CKI
pins become inputs. That is, the TRISC<1:0> value is
ignored.
Additional information on timer modules is available in
the PICmicro™ Mid-Range MCU Family Reference
Manual (DS33023).
R/W-0
R/W-0
PIC16C745/765
bit0
R = Readable bit
W = Writable bit
U = Unimplemented bit,
- n = Value at POR reset
read as ‘0’
DS41124C-page 45