70592C Datasheet, PDF (149/314 Pages) Microchip Technology – High-Performance, 16-bit Microcontrollers

PIC24HJXXXGPX06A/X08A/X10A
13.0 TIMER2/3, TIMER4/5, TIMER6/7
AND TIMER8/9
Note 1: This data sheet summarizes the features
of the PIC24HJXXXGPX06A/X08A/X10A
family of devices. However, it is not
intended to be a comprehensive refer-
ence source. To complement the infor-
mation in this data sheet, refer to Section
11. “Timers” (DS70244) of the
“dsPIC33F/PIC24H Family Reference
Manual”, which is available from the
Microchip website (www.microchip.com).
2: Some registers and associated bits
described in this section may not be
available on all devices. Refer to
Section 4.0 “Memory Organization” in
this data sheet for device-specific register
and bit information.
The Timer2/3, Timer4/5, Timer6/7 and Timer8/9
modules are 32-bit timers, which can also be config-
ured as four independent 16-bit timers with selectable
operating modes.
As a 32-bit timer, Timer2/3, Timer4/5, Timer6/7 and
Timer8/9 operate in three modes:
• Two Independent 16-bit Timers (e.g., Timer2 and
Timer3) with all 16-bit operating modes (except
Asynchronous Counter mode)
• Single 32-bit Timer
• 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
• Time Base for Input Capture and Output Compare
Modules (Timer2 and Timer3 only)
• ADC1 Event Trigger (Timer2/3 only)
• ADC2 Event Trigger (Timer4/5 only)
Individually, all eight of the 16-bit timers can function as
synchronous timers or counters. They also offer the
features listed above, except for the event trigger; this
is implemented only with Timer2/3. The operating
modes and enabled features are determined by setting
the appropriate bit(s) in the T2CON, T3CON, T4CON,
T5CON, T6CON, T7CON, T8CON and T9CON regis-
ters. T2CON, T4CON, T6CON and T8CON are shown
in generic form in Register 13-1. T3CON, T5CON,
T7CON and T9CON are shown in Register 13-2.
For 32-bit timer/counter operation, Timer2, Timer4,
Timer6 or Timer8 is the least significant word; Timer3,
Timer5, Timer7 or Timer9 is the most significant word
of the 32-bit timers.
Note:
For 32-bit operation, T3CON, T5CON,
T7CON and T9CON control bits are
ignored. Only T2CON, T4CON, T6CON
and T8CON control bits are used for setup
and control. Timer2, Timer4, Timer6 and
Timer8 clock and gate inputs are utilized
for the 32-bit timer modules, but an inter-
rupt is generated with the Timer3, Timer5,
Ttimer7 and Timer9 interrupt flags.
To configure Timer2/3, Timer4/5, Timer6/7 or Timer8/9
for 32-bit operation:
1. Set the corresponding T32 control bit.
2. Select the prescaler ratio for Timer2, Timer4,
Timer6 or Timer8 using the TCKPS<1:0> bits.
3. Set the Clock and Gating modes using the
corresponding TCS and TGATE bits.
4. Load the timer period value. PR3, PR5, PR7 or
PR9 contains the most significant word of the
value, while PR2, PR4, PR6 or PR8 contains the
least significant word.
5. If interrupts are required, set the interrupt enable
bit, T3IE, T5IE, T7IE or T9IE. Use the priority
bits, T3IP<2:0>, T5IP<2:0>, T7IP<2:0> or
T9IP<2:0>, to set the interrupt priority. While
Timer2, Timer4, Timer6 or Timer8 control the
timer, the interrupt appears as a Timer3, Timer5,
Timer7 or Timer9 interrupt.
6. Set the corresponding TON bit.
The timer value at any point is stored in the register
pair, TMR3:TMR2, TMR5:TMR4, TMR7:TMR6 or
TMR9:TMR8. TMR3, TMR5, TMR7 or TMR9 always
contains the most significant word of the count, while
TMR2, TMR4, TMR6 or TMR8 contains the least
significant word.
To configure any of the timers for individual 16-bit
operation:
1. Clear the T32 bit corresponding to that timer.
2. Select the timer prescaler ratio using the
TCKPS<1:0> bits.
3. Set the Clock and Gating modes using the TCS
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.
6. Set the TON bit.
© 2011 Microchip Technology Inc.
DS70592C-page 149