From Newsgroup: comp.os.msdos.misc
On Wed, 01 May 2019 20:06:26 +0000, T. Ment wrote:
On 01 May 2019 17:23:03 GMT, Mateusz Viste wrote:
UMBPCI always worked perfectly for me.
I have one computer where it's perfect. All the others, DMACHK says
ISA-DMA fails in UMBs. It reports the ISA-DMA failure with both UMBPCI
and EMM386.
So it's not clear if DMACHK has a problem, or if UMBPCI is fully safe,
or not. They warn about the ISA-DMA problem in the readme though, so I presume they know what they're talking about.
They say ISA-DMA in UMBs is trouble when you load SMARTDRV high and
cache the floppy drive. Maybe I will try that, and see what happens to a (test) floppy disk.
Oh, I see - but I never load stuff that uses DMA high. That's probably I
have no problems. I do remember however, many years ago, getting into
problems with some CD driver (I think). Not loading it high resolved the issue, that's when I learned never to trust DMA when running from within
UMB.
I do not use EMM386 at all, don't like V86 mode.
What's wrong with V86 mode?
I don't like having some extra layer between me and the hardware. When my system crashes with an "invalid opcode" or similarly terrifying message,
I don't want having to second-guess whether it's my program that's buggy,
or the V86 monitor that went south. If bad stuff happens on bare
hardware, then at least I know who to blame (the hardware, of course).
Mateusz
--- Synchronet 3.17c-Linux NewsLink 1.110