Hi! Could someone please comment on the following info from the Intel: : 8259/82C59 : Spurious IRQ7 : : In some applications, problem with a spurious IRQ7 might exist. : For example, a spurios IRQ7 will occur under the following condition: : : While the device is performing extensive I/O operations : (IN AL, DX; OUT DX, AL), an external signal triggers IRQ3. : Spurious enabling of IRQ7 and occassional losing of IRQ3 will be : the outcome of this condition. : : Design Consideration: : : - A spurious IRQ7 occurs, in the 8259, if any interrupt request : duration is too short or hasn't met the setup time required by : the 8259A. : : - This is a standard 8259 behavior under specific conditions. : IRQ7 is triggered when IRQ7 is enabled and is requested : OR : when an interrupt request clears (by itself) before the CPU : services the request. A software solution would be to write : an IRQ7 handler that checks the various possible requesters : and to handle any "missed" interrupts from any of those : requesters. (http://support.intel.com/support/controllers/peripheral/7507.htm) -- Ruslan Ermilov Sysadmin and DBA of the [EMAIL PROTECTED] United Commercial Bank, [EMAIL PROTECTED] FreeBSD committer, +380.652.247.647 Simferopol, Ukraine http://www.FreeBSD.org The Power To Serve http://www.oracle.com Enabling The Information Age To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-hackers" in the body of the message
