Doubt in ISR

for say iam using Timer.
in the Timer iam putting one task
is this RTOS stuff or is 'task' just your 'name' for some code?

what will happen if the Timer overflows before the task finished.for first overflow and for subsequent overflows.
assuming you have auto-referesh, the ISR will finish, one instruction in main will be executed and the ISR will be entered again. (if it overflows twice while in the ISR you still only get one reentry)

post or kindly refer any material
the interrupt mecahanism is described in excruciating detail in "the bible"

Erik

here are the links to "the bible"
Chapter 1 - 80C51 Family Architecture:
www.nxp.com/.../80C51_FAM_ARCH_1.pdf

Chapter 2 - 80C51 Family Programmer’s Guide and Instruction Set:
www.nxp.com/.../80C51_FAM_PROG_GUIDE_1.pdf

Chapter 3 - 80C51 Family Hardware Description:
www.nxp.com/.../80C51_FAM_HARDWARE_1.pdf

for say iam using Timer.
in the Timer iam putting one task
is this RTOS stuff or is 'task' just your 'name' for some code?

what will happen if the Timer overflows before the task finished.for first overflow and for subsequent overflows.
assuming you have auto-referesh, the ISR will finish, one instruction in main will be executed and the ISR will be entered again. (if it overflows twice while in the ISR you still only get one reentry)

post or kindly refer any material
the interrupt mecahanism is described in excruciating detail in "the bible"

Erik

here are the links to "the bible"
Chapter 1 - 80C51 Family Architecture:
www.nxp.com/.../80C51_FAM_ARCH_1.pdf

Chapter 2 - 80C51 Family Programmer’s Guide and Instruction Set:
www.nxp.com/.../80C51_FAM_PROG_GUIDE_1.pdf

Chapter 3 - 80C51 Family Hardware Description:
www.nxp.com/.../80C51_FAM_HARDWARE_1.pdf

Thank you Erik

Actually i used task for a user defined function.

i have downloaded all

That is necessary, but not sufficient.

To gain benefit from the doenloads, you need to spend time studying them...

;-)

Hi Andy

Thanks for your advice. But iam not that much cute in studies than hearing from a friend.
hope not killing much time. if not pardon please.

Thanks for your *advice*. But iam not that *much cute* in *studies* than *hearing* from a *friend*.
hope not *killing* much *time*. if not pardon please.

Friends don't read datasheets to friends. Consultants do to their customers.

Thanks for your *advice*. But iam not that *much cute* in *studies* than *hearing* from a *friend*.
hope not *killing* much *time*. if not pardon please.
friends say more wrong things than you will ever read in a datasheet. BTW "the bible" is 20+ years old and I have yet to see someone point out an error in it.

The anazinf thing about reading "the bible" as opposed to asking a friend is that when you have used "the bible" a fw times, you instinctively know where to look when a question comes up.

Erik

This guy ain't *cute*, ain't particularly *smart* and he *kills* me!