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Team,
Please suggest me what is missing/wrong? I'm unable to hit ISR even though the timer is reset and interrupt flag is set.
I'm not using real hardware but running in simulation mode only and for LPC23xx:
My startup code: Vectors LDR PC, Reset_Addr LDR PC, Undef_Addr LDR PC, SWI_Addr LDR PC, PAbt_Addr LDR PC, DAbt_Addr NOP ; Reserved Vector ; LDR PC, IRQ_Addr LDR PC, [PC, #-0x0120]
LDR PC, FIQ_Addr
void InitTimer1() {
/* Timer1 and Preset disabled */ T1TCR = 0x00; /* Timer Counter register, after PR is reset, this inc by 1 */ T1TC = 0x00; /* Prescalar register! Max value for prescalar counter */ T1PR = 0xFFFF; /* Prescale Counter register */ T1PC = 0x0; /* End user has to fill in the match value */ T1MR0 = 0x222; /* Reset TC and interrupt on match */ T1MCR = 0x03; /* 0000 0000 0000 0011 */ }
void InitVIC() {
VICIntSelect &= (~(1 << 5)); /* Timer 1 selected as IRQ */ /* Address of the ISR */ VICVectAddr5 = (unsigned long )Timer1_IRQ_Handler;
VICVectCntl5 = 0x20 | 5; VICIntEnable |= (1 << 5);/* Timer 1: (bit 5) interrupt enabled */
}
void Timer1_IRQ_Handler (void) __irq { unsigned static int i = 0; T0IR = 0x01; /* Clear Timer1 MR0 interrupt */ IOSET0 = ~ (1 << (i+1)); if ( i == 32) i = 1; i++; VICVectAddr = 0x00;/* Dummy write to ACK the VIC */
int main() { InitPLL(); EnableMAM(); SetPeripheralClock(); InitGPIO(); InitTimer1(); InitVIC();
/* Timer1 and Preset Enabled */ T1TCR = 0x01;
/* Rest of the code */ while (1);
-> Since keil LPC23xx.h file does not have VICVectPriority defined <-
It is defined in the LPC23xx.h, I think.
<LPC23xx.h>
/* LPC23xx/24xx VICVectPriority(x)". */ #define VICVectPriority0 (*(volatile unsigned long *)(VIC_BASE_ADDR + 0x200)) #define VICVectPriority1 (*(volatile unsigned long *)(VIC_BASE_ADDR + 0x204)) #define VICVectPriority2 (*(volatile unsigned long *)(VIC_BASE_ADDR + 0x208)) #define VICVectPriority3 (*(volatile unsigned long *)(VIC_BASE_ADDR + 0x20C)) #define VICVectPriority4 (*(volatile unsigned long *)(VIC_BASE_ADDR + 0x210)) #define VICVectPriority5 (*(volatile unsigned long *)(VIC_BASE_ADDR + 0x214)) #define VICVectPriority6 (*(volatile unsigned long *)(VIC_BASE_ADDR + 0x218))
The correct name VICVectPriorityXX was added from version 1.02 of the LPC23xx.h file (2007-09-05).
I started with the LPC23xx chips before it was added.
I've included this in my header file LPC23XX.H but still no luck of interrupt being hit.
Snapshot of the VIC init code is as below:
void InitVIC() { /* No PIN BLOCK HERE as we're using timer interrupt and no external interrupt */ VICIntSelect = 0x00; /* Timer 1 selected as IRQ */ /* Address of the ISR */ VICVectAddr5 = (unsigned long )Timer1_IRQ_Handler; VICVectPriority5 = 0x20 | 0x05; VICIntEnable |= 0x20; /* Timer 1: (bit 5) interrupt enabled */ }
.
The datasheet for the LPC23xx claims:
Bit 0:3 VICVectPriority Selects one of 16 priority levels for the corresponding vectored interrupt. 31:4 - Reserved, user software should not write ones to reserved bits. The value read from a reserved bit is not defined.
So maybe you shouldn't do your 0x20 | 0x05 since that is clearly writing values to reserved bits.
Just write your priority (0..15) into the register. Nothing else. There is no "enable" bit for the priority register. That "enable" bit only existed for the LPC21xx processor in the VICVectCntlXX register.
Setting the priority as 0x05 does not solve the issue.
"Setting the priority as 0x05 does not solve the issue." No, but that doesn't mean you shouldn't fix it, and continue making sure that your code matches the user manual - or reference code. You are spending time on your code, or relying 100% on the forum?
VICIntEnable |= 0x20; /* Timer 1: (bit 5) interrupt enabled */
Bettery write:
VICIntEnable |= 1<<5;
And even better to do:
enum { INT_TIMER1 = 5, }; ... VICIntEnable |= 1 << INT_TIMER1;
By the way - is there a reason why your timer1 interrupt handler is writing to T0IR instead of T1IR?
Another thing. When you finally did use the pre tags to repost your code, it seems like you copied the code from the previous post, instead of copying from the editor - it has the same strange indentation making it hard to read. Note that tab doesn't work well when posting code.
Please find code post again from editor.
T0IR = 0x01; /* Clear Timer1 MR0 interrupt */
It was my mistake, I should have cleared T1IR instead of T0IR, though the comment is clearly referring to T1IR.
Thanks for catching this bug.
I've coded based on the manual but no luck so far. I'm not relying 100% on the forum responses but seeking inputs for techies.
#include <LPC23xx.H> /* LPC23xx definitions */ void Timer1_IRQ_Handler(void) __irq; void InitVIC() { /* No PIN BLOCK HERE as we're using timer interrupt and no external interrupt */ VICIntSelect &= ~(1L<<5); /* Timer 1 selected as IRQ */ /* Address of the ISR */ VICVectAddr5 = (unsigned long )Timer1_IRQ_Handler; VICVectPriority5 = 0x05; VICIntEnable |= 0x20; /* Timer 1: (bit 5) interrupt enabled */ } /* Timer 1 IRQ T0IR: 4bits for MRn and 4bit for CRn 0 - MR0 int 1 - MR1 int 3 - MR3 int 4 - CR0 int 5 - CR1 int 7 - CR3 int */ __irq void Timer1_IRQ_Handler (void) { unsigned static int i = 0; T1IR = 0x01; /* Clear Timer1 MR0 interrupt */ IOSET0 = ~ (1 << (i+1)); if ( i == 32) i = 1; i++; VICVectAddr = 0xFF; /* Dummy write to ACK the VIC */ } void InitTimer1() { /* Timer1 and Preset disabled */ T1TCR = 0x00; /* Timer Counter register, after PR is reset, this inc by 1 */ T1TC = 0x00; /* Prescalar register! Max value for prescalar counter */ T1PR = 0xFFFF; /* Prescale Counter register */ T1PC = 0x0; /* End user has to fill in the match value */ T1MR0 = 0x222; /* Reset TC and interrupt on match */ T1MCR = 0x03; /* 0000 0000 0000 0011 */ } int main() { InitPLL(); EnableMAM(); SetPeripheralClock(); InitGPIO(); InitTimer1(); InitVIC(); /* Timer1 and Preset Enabled */ T1TCR = 0x01; /* Rest of the code */ while (1); }
Regards,
Any assigns to PCONP anywhere?