On Thu, 25 Jul 2002, at 2:00pm, Rich C wrote: > If I were to disable this setting, I could manually assign all my IRQs > based on PCI slots (or ISA slots if I had any.)
See me other post on PCI interrupt routing. :-) ISA cards (be they "legacy" ISA cards or "Plug-and-Play" ISA cards) have all interrupt lines available to their slot. The card itself determines which of those, if any, it will use. Some cards are hard-wired to use only one; some use jumpers or switches; some are controlled via onboard logic. Before ISA PnP, it was common enough to have ISA cards which were configured using software, but each card had its own interface and program for doing so. ISA PnP simply standardizes the interface to the onboard logic which controls resource selection. > If you have the "Reset Configuration Data" setting set to ENABLED, the > BIOS will use the ESCD program to reallocate your resources on every boot. Not exactly. The cards themselves do not determine their configuration, and they need no non-volatile storage. The host computer (either the BIOS, or the OS, or some other program) gives them their configuration. Now, most BIOSes will "remember" PCI and PnP resource allocations between boots. The "Reset Configuration Data" option causes the BIOS to reconfigure all devices and rebuild the ESCD. It is a one-time option -- after the reset is performed, the "Reset Configuration Data" setting will switch back to "Disabled". > Then most BIOSes have a section that allows you to set the assignment of > each IRQ, and sometimes the DMA channels too. The usual settings are > AUTO(ESCD) and MANUAL. When resources are controlled manually, I think you > need to tell the BIOS which bus (ISA OR PCI) the resource belongs to. Basically, if you have any non-PnP cards in your system, the BIOS (and maybe even the OS) has no way of knowing what resources they are using. The options you are talking about allow you to reserve resources for use by non-PnP cards. Using these options will cause the BIOS to *never* allocate those resources for *anything*. In theory, the OS has an advantage here, because the device driver for a non-PnP card might be able to tell the OS what resources the device is using. Or not. ISA PnP is one of those things that, when it works, it works great, and when it doesn't work, you're fscked good. :-/ -- Ben Scott <[EMAIL PROTECTED]> | The opinions expressed in this message are those of the author and do not | | necessarily represent the views or policy of any other person, entity or | | organization. All information is provided without warranty of any kind. | ***************************************************************** To unsubscribe from this list, send mail to [EMAIL PROTECTED] with the text 'unsubscribe gnhlug' in the message body. *****************************************************************
