RayeR wrote:
I see, but it's related to old MBs and chipsets, not mention any modern PCI-E based MBs...
It did reference the Intel document about the removal of PC/PCI in recent ICH chipsets, stating it's game overfor ISA sound cards unless you only use the synth, which is the case. Most of the page focused on boards and chipsets that are reported working well with ISA sound cards.
RayeR wrote:This looks interesting. But I don't understand this:
The DMA controllers can initiate transfers
between the LPC and host bus. Th […]
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This looks interesting. But I don't understand this:
The DMA controllers can initiate transfers
between the LPC and host bus. This provides the option of
adding an LPT or fl oppy controller to the LPC port with DMA
support. But the chipset DMA controller cannot initiate
PCI to host bus transactions. To enable ISA-conform DMA,
the ITE 8888 PCI to ISA bridge integrated on the Kontron
MICROSPACE® MSM-eO(-N) features two additional 8237
DMA controllers.
They admit LPC can do ISA DMA - that is what we need for soundcards but then they write "chipset DMA controller cannot initiate
PCI to host bus transactions" - is it needed? Maybe only for this AMD platform but for Portwell Ruby is the LPC2ISA bridge all that is needed and proved it works (at least on G41+ICH7)
LPC DMA remained in order to avoid breaking support for FDC and ECP parallel ports provided by SuperIO chips, which might be required for industrial purposes. If LPC DMA were removed, modern board would NEVER be able to support floppy drives and parallel ports anymore.
Guess that the "chipset DMA controller cannot initiate PCI to host bus transactions" is what breaks most of the legacy compatibility in ICH6 or later. It not only breaks PCI-ISA, it also breaks whatever sound cards used to support legacy DOS audio (except Aureal Vortex series). In modern AMD chipsets (like 700/800/900 series) the situation is much worse that it's behaving the same way as the Intel chipsets without native PCI (some 5 to 7 series PCHs and all PCHs from 8 series onwards), the legacy functions is completely inaccessible even after loading TSRs (and probably under Windows and Linux as well). It's that fact that makes the AMD/AMI's "ISA DMA virtualization" thing interesting.
From the IT8888 datasheet the PCI-ISA bridge itself does feature 8237 DMA controllers of its own, most likely those are what actually mediate the transactions between the ISA devices and the chipset PC/PCI, though I'm not entirely sure. The PCI-ISA bridges' DMA related pins might have been connected to somewhere even in modern (ICH6+ based) motherboards, though it's not easy to find that out on a PCB that complex.
RayeR wrote:
Yes, industrial MBs don't include overclocking options. Do you have a related microcode in BIOS for your Xeon CPU?
I did insert microcodes into the BIOS. It's just that the board probably has some underlying BIOS or wiring issues (or maybe power management related) that makes things incompatible with LGA771 Xeons. The board recognizes the Xeon correctly, and it can stay running under DOS and other system diagnostic programs for quite a while (I could run MemTest+ with two or more passes without issues), just it would crash once in a while with a different BSoD under Windows. Sometimes it can even miscompute things, causing CRC and data errors that goes away the next time the program runs, and after crash, keyboards would sometimes stop responding the next boot, requiring a hard reset to get the keyboard back running.
It seems most insudstrial motherboards aren't meant to be used to run out-of-spec stuffs. I also tried modding the BSEL of a Pentium D 965 from 266 (LLL) down to 200 (LHL) for a 865-based motherboard (IMB200) in hope it can boot properly, but still not successful. No matter the mod, the board would either not post or give it an incorrect, non-bootable bus clock (used to be 33MHz, this time I managed to make it 40MHz).
The only purpose for those boards is to provide additional I/O ports that consumer motherboards hardly provide (RS232/485/422, ECP Parallel, GPIO, etc.), yet still very useful in industrial purposes. They only support whatever hardware the document mentions, and that'd be the end of the line.
RayeR wrote:
BTW I just found this PC/104 http://c1170156.r56.cf3.rackcdn.com/UK_ADL_MM … IO-R-01_2DS.pdf expansion board by Adlink using the same Fintek LPC2ISA so if some wiring would be done to LPC header on MB and from PCI/104 pin connector to an ISA slot it might work. But I couldn't find any e-shop offering this board and no idea about price. I would expect a nasty $$$ for industrial HW...
I'm not sure about the possibility given the board itself might be rare. For desktop motherboard, the TPM header, which is often left unused, is connected to the MB using LPC, and might be able to be used for other purposes. It's just how the wiring would turn out...