pic32mx320f064h Microchip Technology Inc., pic32mx320f064h Datasheet - Page 276

• Manufacturer Part Number: pic32mx320f064h
• Description: 64/100-pin General Purpose, 32-bit Flash Microcontrollers
• Manufacturer: Microchip Technology Inc.

PIC32MX FAMILY
13.5
Timer1 can generate an interrupt on a period match
event or a gate event, caused by the falling edge of the
external gate signal.
Timer1 sets the interrupt flag bit, T1IF (IFS0<4>),
whenever a Timer1 event is generated. Refer to a spe-
cific Timer mode for details regarding event conditions.
When a Timer1 event is generated, the interrupt flag bit
is set within 1 PBCLK + 2 SYSCLK cycles. If Timer1
Interrupt Enable bit is set, T1IE (IEC0<4>) = 1, an
interrupt is generated.
The Timer1 module is enabled as a source of interrupts
through its respective interrupt enable bit, T1IE
(IEC0<4>). The Timer1 Interrupt Flag, T1IF (IFS0<4>),
must be cleared in software.
The interrupt priority level bits and interrupt subpriority
level bits must be also be configured:
• T1IP<2:0> (IPC1<4:2>)
• T1IS<1:0> (IPC1<1:0)
Setting Timer1 interrupt priority level = 0 effectively
disables the timer’s ability to generate an interrupt.
In addition to enabling the Timer1 interrupt, an Interrupt
Service Routine, ISR, is generally required. Below is a
partial code example of an ISR.
EXAMPLE 13-5:
EXAMPLE 13-6:
DS61143A-page 274
void __ISR(TIMER_1_VECTOR, IPL3) T1_Interrupt_ISR(void)
{
}
Note:
Note:
T1CON = 0x0
TMR1 = 0x0;
PR1 = 0xFFFF;
IPC1SET = 0x000C;
IPC1SET = 0x0001;
IFS0CLR = 0x0010;
IEC0SET = 0x0010;
T1CONSET = 0x8000;
... perform application specific operations in response to the interrupt
IFS0CLR
Timer Interrupts
It is the user’s responsibility to clear the
corresponding interrupt flag bit before
returning from an ISR.
The timer ISR code example shows MPLAB
manual regarding support for ISRs.
= 0x0010;
TIMER INTERRUPT AND PRIORITIES
TIMER ISR
// Set prescaler at 1:1, internal clock source
// Clear timer register
// Load period register
// Set priority level=3
// Set subpriority level=1
// Could have also done this in single
// operation by assigning IPC1SET = 0x000D
// Clear Timer interrupt status flag
// Enable Timer interrupts
// Start Timer
// Be sure to clear the Timer 1 interrupt status
// Stop the Timer and Reset Control register
Advance Information
®
C32 C Compiler specific syntax. Refer to your compiler
© 2007 Microchip Technology Inc.