it’s my own project which incorporates both bridge and sound chips on a single pcb. this special header on the mobo inspired me trying it. yes master# signal is pulled up to 5v line via 4.7k resistor.

6300esb datasheet has e2h register related to legacy sound cards io, but it’s stated as not validated whatever it means. i decided to give a try but stuck at the very beginning.

anthony wrote on 2026-02-14, 22:18:

it’s my own project which incorporates both bridge and sound chips on a single pcb. this special header on the mobo inspired me trying it. yes master# signal is pulled up to 5v line via 4.7k resistor.

6300esb datasheet has e2h register related to legacy sound cards io, but it’s stated as not validated whatever it means. i decided to give a try but stuck at the very beginning.

Hmmm... looks like older ICHs have only two generic decode ranges (E4h and ECh) for LPC, compared to later ones which has four. This kind of matches the functionality of the Winbond LPC-ISA bridge, W83626.

The register E2H you mentioned is no longer present on ICH5 datasheet. Bits related to sound cards in E6H are also marked as "Reserved" there. I don't think they're that relevant, however, as at least with MIDI and SB decode ranges they are too few for some modern sound cards, including GUS.

I think you'll have to look for earlier boards (late PIII or early P4) with ISA slots that incorporated LPC-ISA instead of PCI-ISA, to see whether these decode range registers had any use back then.

Alright, what is the differecne between 0.3 and 0.4 revisions of this bridge board?