Re: Triton DMA

Doug Ledford (
Sat, 29 Nov 1997 20:17:21 -0600 (CST)

On 30-Nov-97 Linus Torvalds wrote:
>In article <65q0g9$6nu$>,
>H. Peter Anvin <> wrote:
>>I guess I don't really understand the quest to turn IDE into SCSI,
>>especially since SCSI is *still* very much more versatile than IDE; I
>>have yet to see an IDE scanner...
>Well, SCSI may be more versatile, but I have yet to get a single report
>about problems with IDE because of bad termination.

Sure you have. You just haven't documented it as such. Problem reports from
people who have enabled Triton Bus Master support, reports of IDE disk
corruption and timeout/reset cycles, etc. Any of these problem reports could
have been caused by the IDE equivelant of non-termination (aka, too long of
an IDE cable or running an entirely unterminated IDE bus at too high of a PIO
speed). Because people can't change the settings and make the problem go
away doesn't mean it hasn't cropped up in other guises :)

>The fact is that neither IDE not SCSI is perfect. IDE wins hands down
>in price and ease of use, while SCSI wins on high-end performance and
>flexibility. Which one you consider to be more important depends on the

Ease of use falls to SCSI whenever you have a complex system to build. Like
maybe one with more than 4 devices total where you would run out of IDE
connections on a typical system. That really only leaves price. So, when
I'm building a computer that I have to use 12 to 16 hours a day, depend upon
day in an day out, and make a living from, I don't go bargain basement. I
go with what works, is reliable, gets the job done quickly, and that won't
spend half of its usefull life in the mail to some warranty repair center.

Now, when Grandma is tinkering with her new toy that lets her get into a
steamy conversation in some chat room, I'm sure she couldn't care less if
her system uses IDE or SCSI devices :)

>There are lots of people who think that SCSI is inherently better.
>Personally I consider that to be a very limited view of the situation.

It has its advantages, regardless of whether or not a person has to know a
little about what they are doing to make it reliable (that or they actually
have to read a manual and understand it, ugh, how could we ever expect
people to do that).

>As to IDE scanners - a few years ago the selling point of SCSI oevr IDE
>(at least according to SCSI proponents) was that you could buy CD-ROM
>drives etc for SCSI without having to buy an extra card. Anybody who
>buys a SCSI CD-ROM these days has too much money and too little sense.

Until you take into consideration things like the SCSI CD-ROM I have has
been going well for about 2 1/2 years. In 1 1/2 years my only IDE CD-ROM
has died twice. Mass market consumer electronics does not mean decent
electronics. In many cases the old adage "You get what you paid for" still
holds true.

>IDE has had a _lot_ of development due to mass market issues. Many
>technical people look at technical specifications rather than at market
>issues, and that's not necessarily the best thing to do.

I look at market issues very often, and quite frankly, what some people are
willing to buy scares the crap out of me sometimes :)

E-Mail: Doug Ledford <>
Date: 29-Nov-97
Time: 20:17:22