Microchip Technology MA240017 Data Sheet
2008-2011 Microchip Technology Inc.
DS39927C-page 117
PIC24F16KA102 FAMILY
13.0
TIMER2/3
The Timer2/3 module is a 32-bit timer, which can also be
configured as two independent 16-bit timers with
selectable operating modes.
As a 32-bit timer, Timer2/3 operates in three modes:
• Two independent 16-bit timers (Timer2 and
configured as two independent 16-bit timers with
selectable operating modes.
As a 32-bit timer, Timer2/3 operates in three modes:
• Two independent 16-bit timers (Timer2 and
Timer3) with all 16-bit operating modes (except
Asynchronous Counter mode)
Asynchronous Counter mode)
• Single 32-bit timer
• Single 32-bit synchronous counter
• Single 32-bit synchronous counter
They also support these features:
• Timer gate operation
• Selectable prescaler settings
• Timer operation during Idle and Sleep modes
• Interrupt on a 32-bit Period register match
• A/D Event Trigger
Individually, both of the 16-bit timers can function as
synchronous timers or counters. They also offer the
features listed above, except for the A/D event trigger
(this is implemented only with Timer3). The operating
modes and enabled features are determined by setting
the appropriate bit(s) in the T2CON and T3CON
registers. T2CON and T3CON are provided in generic
form in
• Timer gate operation
• Selectable prescaler settings
• Timer operation during Idle and Sleep modes
• Interrupt on a 32-bit Period register match
• A/D Event Trigger
Individually, both of the 16-bit timers can function as
synchronous timers or counters. They also offer the
features listed above, except for the A/D event trigger
(this is implemented only with Timer3). The operating
modes and enabled features are determined by setting
the appropriate bit(s) in the T2CON and T3CON
registers. T2CON and T3CON are provided in generic
form in
and
, respectively.
For 32-bit timer/counter operation, Timer2 is the least
significant word (lsw) and Timer3 is the most significant
word (msw) of the 32-bit timer.
significant word (lsw) and Timer3 is the most significant
word (msw) of the 32-bit timer.
To configure Timer2/3 for 32-bit operation:
1.
1.
Set the T32 bit (T2CON<3> = 1).
2.
Select the prescaler ratio for Timer2 using the
TCKPS<1:0> bits.
TCKPS<1:0> bits.
3.
Set the Clock and Gating modes using the TCS
and TGATE bits.
and TGATE bits.
4.
Load the timer period value. PR3 will contain the
msw of the value while PR2 contains the lsw.
msw of the value while PR2 contains the lsw.
5.
If interrupts are required, set the interrupt enable
bit, T3IE. Use the priority bits, T3IP<2:0>, to set
the interrupt priority.
While Timer2 controls the timer, the interrupt
appears as a Timer3 interrupt.
bit, T3IE. Use the priority bits, T3IP<2:0>, to set
the interrupt priority.
While Timer2 controls the timer, the interrupt
appears as a Timer3 interrupt.
6.
Set the TON bit (= 1).
The timer value, at any point, is stored in the register
pair, TMR<3:2>. TMR3 always contains the msw of the
count, while TMR2 contains the lsw.
To configure any of the timers for individual 16-bit
operation:
1.
pair, TMR<3:2>. TMR3 always contains the msw of the
count, while TMR2 contains the lsw.
To configure any of the timers for individual 16-bit
operation:
1.
Clear the T32 bit in T2CON<3>.
2.
Select the timer prescaler ratio using the
TCKPS<1:0> bits.
TCKPS<1:0> bits.
3.
Set the Clock and Gating modes using the TCS
and TGATE bits.
and TGATE bits.
4.
Load the timer period value into the PRx register.
5.
If interrupts are required, set the interrupt enable
bit, TxIE; use the priority bits, TxIP<2:0>, to set
the interrupt priority.
bit, TxIE; use the priority bits, TxIP<2:0>, to set
the interrupt priority.
6.
Set the TON bit (TxCON<15> = 1).
Note:
This data sheet summarizes the features
of this group of PIC24F devices. It is not
intended to be a comprehensive refer-
ence source. For more information on
Timers, refer to the “PIC24F Family Refer-
ence Manual”
of this group of PIC24F devices. It is not
intended to be a comprehensive refer-
ence source. For more information on
Timers, refer to the “PIC24F Family Refer-
ence Manual”
, Section 14. “Timers”
(DS39704).
Note:
For 32-bit operation, T3CON control bits
are ignored. Only T2CON control bits are
used for setup and control. Timer2 clock
and gate inputs are utilized for the 32-bit
timer modules, but an interrupt is
generated with the Timer3 interrupt flags.
are ignored. Only T2CON control bits are
used for setup and control. Timer2 clock
and gate inputs are utilized for the 32-bit
timer modules, but an interrupt is
generated with the Timer3 interrupt flags.