Interrupt Problems

[Nikki]

3.116 PIC16F628

I wonder if someone could enlighten me as to why as soon as I enable interrupts for any specific timer overflow, the interrupt is executed straight away.

I'm doing something like this:

setup_timer_1(T1_INTERNAL|T1_DIV_BY_8);
set_timer1(0xCF2C);// 100ms delay
enable_interrupts(int_timer1); // INT_TIMER1 execute here

Do I need to clear some flags to fix this?

On another subject. I'm trying to debug some code using MPLAB Simulator and have 16 bit pointers enabled in CCS, but the register and watch windows show a wrap around. I have a register at 0x7F and when its contents is changed, the contents of 0xFF and 0x17F also show a change. Is this correct for MPLAB?

Thanks,

Nikki
___________________________
This message was ported from CCS's old forum
Original Post ID: 8093

[Nikki]

Ignore my second question. The datasheet says "accesses 70h-7fh" for these locations, so I understand the reason.

Nikki

:=On another subject. I'm trying to debug some code using MPLAB Simulator and have 16 bit pointers enabled in CCS, but the register and watch windows show a wrap around. I have a register at 0x7F and when its contents is changed, the contents of 0xFF and 0x17F also show a change. Is this correct for MPLAB?
___________________________
This message was ported from CCS's old forum
Original Post ID: 8094

[Mark]

Try this. I would suggest that you always disable the timer before changing its value:

setup_timer_1(T1_DISABLED);
PIR1.TMR1IF = 0 // this assumes you have a structure defined or something like bit_clear(PIR1, TMR1IF) or bit_clear(PIR1,0)
set_timer1(0xCF2C);// 100ms delay
setup_timer_1(T1_INTERNAL|T1_DIV_BY_8);
enable_interrupts(int_timer1); // INT_TIMER1 execute here

Regards,
Mark

:=3.116 PIC16F628
:=
:=I wonder if someone could enlighten me as to why as soon as I enable interrupts for any specific timer overflow, the interrupt is executed straight away.
:=
:=I'm doing something like this:
:=
:=setup_timer_1(T1_INTERNAL|T1_DIV_BY_8);
:=set_timer1(0xCF2C);// 100ms delay
:=enable_interrupts(int_timer1); // INT_TIMER1 execute here
:=
:=Do I need to clear some flags to fix this?
:=
:=On another subject. I'm trying to debug some code using MPLAB Simulator and have 16 bit pointers enabled in CCS, but the register and watch windows show a wrap around. I have a register at 0x7F and when its contents is changed, the contents of 0xFF and 0x17F also show a change. Is this correct for MPLAB?
:=
:=Thanks,
:=
:=Nikki
___________________________
This message was ported from CCS's old forum
Original Post ID: 8095

[Mark]

Try this. I would suggest that you always disable the timer before changing its value:

setup_timer_1(T1_DISABLED);
PIR1.TMR1IF = 0 // this assumes you have a structure defined or something like bit_clear(PIR1, TMR1IF) or bit_clear(PIR1,0)
set_timer1(0xCF2C);// 100ms delay given a clock of 4MHz
setup_timer_1(T1_INTERNAL|T1_DIV_BY_8);
enable_interrupts(int_timer1); // INT_TIMER1 execute here

Regards,
Mark

:=3.116 PIC16F628
:=
:=I wonder if someone could enlighten me as to why as soon as I enable interrupts for any specific timer overflow, the interrupt is executed straight away.
:=
:=I'm doing something like this:
:=
:=setup_timer_1(T1_INTERNAL|T1_DIV_BY_8);
:=set_timer1(0xCF2C);// 100ms delay
:=enable_interrupts(int_timer1); // INT_TIMER1 execute here
:=
:=Do I need to clear some flags to fix this?
:=
:=On another subject. I'm trying to debug some code using MPLAB Simulator and have 16 bit pointers enabled in CCS, but the register and watch windows show a wrap around. I have a register at 0x7F and when its contents is changed, the contents of 0xFF and 0x17F also show a change. Is this correct for MPLAB?
:=
:=Thanks,
:=
:=Nikki
___________________________
This message was ported from CCS's old forum
Original Post ID: 8096

[Neutone]

When you enable the interupt the timer has already overflowed and set the interupt bit. Clear the interupt bit (overflow bit) before enabeling the interupt.


:=3.116 PIC16F628
:=
:=I wonder if someone could enlighten me as to why as soon as I enable interrupts for any specific timer overflow, the interrupt is executed straight away.
:=
:=I'm doing something like this:
:=
:=setup_timer_1(T1_INTERNAL|T1_DIV_BY_8);
:=set_timer1(0xCF2C);// 100ms delay
:=enable_interrupts(int_timer1); // INT_TIMER1 execute here
:=
:=Do I need to clear some flags to fix this?
:=
:=On another subject. I'm trying to debug some code using MPLAB Simulator and have 16 bit pointers enabled in CCS, but the register and watch windows show a wrap around. I have a register at 0x7F and when its contents is changed, the contents of 0xFF and 0x17F also show a change. Is this correct for MPLAB?
:=
:=Thanks,
:=
:=Nikki
___________________________
This message was ported from CCS's old forum
Original Post ID: 8100

[Nikki]

Thanks everyone for the answer!

Nikki
___________________________
This message was ported from CCS's old forum
Original Post ID: 8105