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Hello, when I list the PCI devices I get one, for which I can't find any driver. It is Vendor ID 0x8086 and Device ID 0x1237. pcidatabase.com says, it is "PCI & Memory", and I found it is "Intel 82440FX". After reading the Intel manual, I still don't know what I can do with it. Can this device be configured, or can I get information about the system from it? I have a PCI driver that uses it, but I don't know how to communicate with it.....

Can I ask it for example, how much memory the system has? I heard some OSes don't use the BIOS to detect the memory, and since manual probing is not the bes methode. Do they use the 82440FX to get the memory map?

The 82440FX is the chipset. You are implicitly programming it when you program the PIC, the PIT, keyboard controller, and quite likely a lot of more recent circuitry, such as the i/o apic, as well. Originally they were separate chips, and some of them are still available as separate chips, but on motherboards nowadays they are usually bundled into a single chip.

I heard some OSes don't use the BIOS to detect the memory

I don't know which operating system you are talking about, but Windows uses the BIOS, and so does Linux. If you google it, you can find Linux programmers complaining, because they consider the EFI memory map to be a poor relation of the memory map supplied by the BIOS function.

Hi,

teodori wrote:Hello, when I list the PCI devices I get one, for which I can't find any driver. It is Vendor ID 0x8086 and Device ID 0x1237. pcidatabase.com says, it is "PCI & Memory", and I found it is "Intel 82440FX". After reading the Intel manual, I still don't know what I can do with it. Can this device be configured, or can I get information about the system from it? I have a PCI driver that uses it, but I don't know how to communicate with it.....

Go to this Intel web page and scroll down until you see the link for "Intel® 440FX PCIset - 82441FX PCI and Memory Controller (PMC) and 82442FX Data Bus Accelerator (DBX) Datasheet". This datasheet describes the chipset's north-bridge (Vendor ID 0x8086 and Device ID 0x1237).

Note: As far as I know; this chipset is "sort of emulated" by Bochs and Qemu, in that some parts of it aren't emulated at all and some things that never existed in this chipset were added.


Cheers,

Brendan

Okay thank you. Now I see it clearer.