PIC18FXX39 Datasheet, PDF (107/322 Pages) Microchip Technology – Enhanced FLASH Microcontrollers with Single Phase Induction Motor Control Kernel

PIC18FXX39
12.0 TIMER2 MODULE
The Timer2 module is an 8-bit timer with a selectable
8-bit period. It has the following features:
• Input from system clock at FOSC/4 with
programmable input prescaler
• Interrupt on timer-to-period match with
programmable postscaler
The module has three registers: the TMR2 counter, the
PR2 period register, and the T2CON control register.
The general operation of Timer2 is shown in
Figure 12-1.
Additional information on the use of Timer2 as a
time-base is available in Section 15.0 (PWM Modules).
FIGURE 12-1:
TIMER2 BLOCK DIAGRAM
Note:
In PIC18FXX39 devices, Timer2 is used
exclusively as a time-base for the PWM
modules in motor control applications. As
such, it is not available to users as a
resource. Although their locations are
shown on the device data memory maps,
none of the Timer2 registers are directly
accessible. Users should not alter the
values of these registers.
FOSC/4
Prescaler
1:1, 1:4, 1:16
(ProMPT Module)
TMR2
RESET
(TMR2 = PR2)
Comparator
Postscaler
1:1 to 1:16
TMR2
Output
Sets Flag
bit TMR2IF
PR2
(ProMPT Module)
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Preliminary
DS30485B-page 107