real time clock interrupt issue
Posted: Thu Jun 07, 2012 6:08 am
Hi,
I've my own OS for x86 arch.
I use a DOS program to prepare MBR and copy OS to HDD. In my system I also have a watchdog board so this program, during boot time, refreshes WD timer until OS starts execution.
This utility works well on Intel Pentium M CPU board. If I try to use it on a new Intel Atom or Intel Core i7 CPU boards it has a strange behaviour.
In details the program assigns my own ISR to IRQ 8 line interrupt call (reserved by BIOS to onboard RTC) with a simple call:
_dos_setvect (0x70, myOwnHandler);
The ISR works fine. The watchdog board is correctly refreshed...
... but during the copy of files from usb to hard disk and then from hard disk to usb pen (for check purpose) the ISR is not served and the watchdog turns-off.
Can you help me?
Thanks.
Context:
C program (MS VS compiler), DOS, CPU Intel Atom, SSD (solid state disk), USB 2.0
Note:
Pentium M board has IDE HDD. Atom board has SATA SSD (compatibility mode selected in BIOS).
I've my own OS for x86 arch.
I use a DOS program to prepare MBR and copy OS to HDD. In my system I also have a watchdog board so this program, during boot time, refreshes WD timer until OS starts execution.
This utility works well on Intel Pentium M CPU board. If I try to use it on a new Intel Atom or Intel Core i7 CPU boards it has a strange behaviour.
In details the program assigns my own ISR to IRQ 8 line interrupt call (reserved by BIOS to onboard RTC) with a simple call:
_dos_setvect (0x70, myOwnHandler);
The ISR works fine. The watchdog board is correctly refreshed...
... but during the copy of files from usb to hard disk and then from hard disk to usb pen (for check purpose) the ISR is not served and the watchdog turns-off.
Can you help me?
Thanks.
Context:
C program (MS VS compiler), DOS, CPU Intel Atom, SSD (solid state disk), USB 2.0
Note:
Pentium M board has IDE HDD. Atom board has SATA SSD (compatibility mode selected in BIOS).