to my personal understanding, intel82371eb/via686b are the latest southbridges that provide native isa slots, all isa slots on later boards are provided by third party chips that creates an isa bus.
A bump in this thread... I've been thinking for a while...
EDIT: Post update.
It seems there are something worth noting. I just checked the datasheets of ICH5, ICH6, and 7-series PCH and apparently, entries about PC/PCI were indeed documented in ICH5, but no longer present in ICH6 and onwards. Apparently PC/PCI used some dedicated REQ/GNT signals, REQ#[A:B] and GNT#[A:B], which in ICH5's case, for example, REQ5# and GNT5# can be used by PC/PCI as REQB# and GNTB#. These signals are no longer present in ICH6 and onwards, nor PCH, as they only have four PCI REQ/GNT signals instead of ICH5's six, and don't appear to support PC/PCI over these signals. LPC DMA (including the legacy interrupt controller and DMA controller pairs) seems to have always been there, probably only meant for interfaces over SuperIO.
Not having proper ISA DMA support does not prevent the PCI-ISA bridge from properly enumerating and configuring the ISA audio card (including ISA PnP ones), it just cannot produce any sound, regardless of operating systems. FM (and probably MIDI) which doesn't require DMA will still work.
wrote:Makes me wonder if this has any truth to it ?: […]
Makes me wonder if this has any truth to it ?:
Intel chipsets since Sandy Bridge once again have a system DMA
capabilityhttp://www.osronline.com/showThread.CFM?link=238574
And will we now be able to find SandyBridge mobos with ISA slots ? 🤣 🤣
For the time being I know no other known means to get working ISA DMA, at least over PCI, and the words about Sandy Bridge having a system DMA... I don't know what this "system DMA"'s nature is yet (especially since LPC DMA was actually always present in Intel's chipsets), and whether this can make ISA DMA work over PCI is still unknown and I've found nothing about it. However, like I said before, almost all ICH6+ based motherboards with ISA stated clear in their datasheets that the ISA slots are slave-only, at least in one of all places, but this was not the case for PCH-based motherboards... While ADEK stated no DMA on MS-98A9 on their ATX motherboards page, but that was the only place that mentioned about such for a PCH-based motherboard, and it was rather unclear since that board has a variant without the ISA slot, and the manual found on MSI was also for such a variant. No statements on whether iBASE MB970VF/MB970F have working DMA or not were found for now, but given it's using IT8888G, a PCI-ISA bridge, odds for it having working DMA are, IMO, very low, unless the so-called Sandy Bridge system DMA can be used as a workaround.
As such, for now, ICH5 is the farthest one can go for ISA slots with working ISA DMA for audio cards (and yeah, limited to AGP cards only). There are actually some 865/875 based LGA775 boards with ISA slots that properly support the dual-core Pentium D as well, such as Axiomtek IMB200.
EDIT3: UPDATE (Nov 22, 2014). I just got myself an IEI IMBA-G412ISA-R20. After testing it for a bit, I was not able to get working sound output out of my CT3110 despite I've reserved IRQ 5 and DMA 1&5 for ISA in its BIOS and have BLASTER environment variable set. At least FM still works as it should. So this board appears just like any other post-ICH5 ISA motherboards which ISA DMA is not possible using PCI/ISA bridges, as tests in CTCU fails on DMA and DIAGNOSE complains no usable DMA channel. Maybe there are something else needed for that board as it's quite interesting for an industrial board to include options regarding Legacy ISA DMA that appears to be doing nothing (The board's BIOS actually has a good deal of features regarding ISA. Aside from PCI/PnP configurations, it also includes options to enable 15-16M memory hole and to configure reserved memory areas for ISA devices).
I'll just leave this right here 😊
http://ipc.msi.com/product/pages/ipc/MS98A9
wrote:I'll just leave this right here 😊
http://ipc.msi.com/product/pages/ipc/MS98A9
We've discussed boards like this to death in other threads, just because it has an ISA slot doesn't mean it's fully functional for the purposes of retro enthusiasts.
"I see a little silhouette-o of a man, Scaramouche, Scaramouche, will you
do the Fandango!" - Queen
Stiletto
wrote:wrote:I'll just leave this right here 😊
http://ipc.msi.com/product/pages/ipc/MS98A9We've discussed boards like this to death in other threads, just because it has an ISA slot doesn't mean it's fully functional for the purposes of retro enthusiasts.
Doesn't the chipset used in ivybridge/sandybridge systems have dma support for isa slots?
wrote:Doesn't the chipset used in ivybridge/sandybridge systems have dma support for isa slots?
DMA support in newest processors doesn't cover ISA DMA. Like LSS10999 wrote in his post, it's only LPC DMA - completely useless for ISA sound cards and other ISA DMA-dependent devices.
wrote:wrote:I'll just leave this right here 😊
http://ipc.msi.com/product/pages/ipc/MS98A9We've discussed boards like this to death in other threads, just because it has an ISA slot doesn't mean it's fully functional for the purposes of retro enthusiasts.
However just a petty nitpick but the original post just said the fastest with an ISA slot. It doesn't say it has to be fully functional
Hello,
just got an MB960AF board to play around with and wanted to let you guys know, I tested with a SB16 card and was able to get OPL and MPU working, though no digitized sounds.
Diagnose.exe reports "failure to set low DMA". So no DMA / PCPCI support out of the box.
Here's the ISA bridge datasheet:
http://www.ite.com.tw/uploads/product_downloa … .9_05162005.pdf
Regards
locutus
for more Retro-related tidbits follow me on X under @ChrisR3tro.
wrote:Hello, […]
Hello,
just got an MB960AF board to play around with and wanted to let you guys know, I tested with a SB16 card and was able to get OPL and MPU working, though no digitized sounds.
Diagnose.exe reports "failure to set low DMA". So no DMA / PCPCI support out of the box.
Here's the ISA bridge datasheet:
http://www.ite.com.tw/uploads/product_downloa … .9_05162005.pdfRegards
locutus
IT8888G is a common PCI-ISA bridge used on those industrial boards. It's the chipset that no longer supports the functions (PC/PCI) needed to get ISA DMA functional. PC/PCI was deprecated by Intel on their chipsets since ICH6, so any future boards with ISA slots will NOT have DMA functionality, unless the board is based on ICH5 or earlier (which corresponds to i865/875 or earlier).
