On Thu, Jan 16, 2003 at 10:54:07PM +0100, Henrik Ostergaard Madsen wrote: > Hi there. > > I am trying to write a userspace 'driver' for a hardware watchdog on an > industrial PC (a Jumptec, to be precise). > > This watchdog is setup and controlled by executing an interrupt 21, > service 0xe000 and 0xe001 to the BIOS interrupt service routine. > > I do not have to receive anything, 'just' to execute such interrupts, > controlling the value of the ax, bx, cx and dx registers. It will run as > root. It is not timing critical. > > Being a Linux newbie, I have not been able to find out how to do this. > Standard assembler will not allow a direct "int $0x15", and I have not > found anything in the syscalls indicating a possibility for such a thing. > > So my question is: What's the easiest way to do it? And where is that > documented? Hmm, there are two choices, the 'easiest' is to go into vm86 mode and send the interrupt there, but that is rather kludgie and probably not very efficiant, the best way would be to just write the stuff yourself using io ports, i doubt that it is so hard, as long as you can find specs for it. -- Mark Zealey (aka JALH on irc.oftc.net: #zealos and many more) mark@zealos.org; mark@itsolve.co.uk UL++++>$ G!>(GCM/GCS/GS/GM) dpu? s:-@ a17! C++++>$ P++++>+++++$ L+++>+++++$ !E---? W+++>$ !w--- r++ !t---?@ !X---? !R- !tv b+ G+++ e>+++++ !h++* r!-- y -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
