Contents | < Browse | Browse >
%% Reader Mail %%
Subject: Reader response regarding GVP 040 Combo review/AR226
In response to the Comprehensive GVP Combo '040 accelerator test in AR226:
Maxwell Daymon has made a very thorough job on the test, and we thank him for
that, but there are some both minor and major fact errors in the review, which
I'd like to point out, as not to confuse others.
First, Maxwell claims that DMA host adaptors as a rule are subject to serial
port hardware overruns. While this isn't false in some cases (mainly GVP has
problems), it certainly isn't true in most. Commodore DMA host adaptors
generally behave very nicely, and the A3000 H/A is a very serial-friendly
dude, since it hardly uses up any bus time at all during transfers. due to
it's 32-bit wide, 25MHz high bandwidth architecture. A normal harddisk running
at the top of it's lungs will generally only require a few percent of the
A3000's bus, and even with the SCSI bus fully saturated, about 75% bus time
should be available for the serial.device interupt server.
And one should realize: having a CPU-polled H/A is no guarrantee against
overruns, they rear their ugly head even in that camp. The benefit in this
case of having a DMA H/A, is that not all CPU-time is consumed during harddisk
The thing that causes these serial overruns in the first case is the size of
the DMA packets being sent out on the SCSI bus. GVP adaptors use very large
packets (probably to squeeze out some extra performance), while most other DMA
adaptors use more moderate sizes. This can be adjusted with the MAXTRANSFER
parameter. Toying with it will *not* destroy anything, altough it's a good
idea to keep note of the original value, since increasing it might cause
undesirable system operation (serial overruns, glitches in module replayers
etc) while the harddisks are working. Decreasing it on the other hand, might
reduce file transfer performance. GVPPatch reduces the maxtransfer only while
the internal serial port is open; and sets it to 512 bytes. That's why your
harddisks will reach almost floppydisk performance during file transfers. As a
general rule: if it ain't broke, don't fix it! That means: fiddle only with
the maxtransfer values if you have serial overrun problems, and try first to
use GVPPatch (if you have a GVP H/A, that is).
It might also be a good idea to switch serial.device for BaudBandit.device
(v1.4c is the most recent, to my knowledge). This is a stripped-down serial
handler (only RTS/CTS handshake and 8N1 serial parameters), but it's blazingly
fast, and uses substantially less CPU time than Commodore's device. Even up to
57kbps could be possible on an unaccelerated machine. Unfortunately, it
doesn't work very well in some systems, however. Try it out, if it gurus,
throw it out. 8^)
Maxwell also says that the A3000 is SCSI1, while the GVP card is SCSI2. That
is incorrect, both host adaptors utilizes the SCSI2 command set, in a beta
version. This is due to the fact that they both use the same Western Digital
SCSI bus controller chip, one that is known as the "00-04 PROTO" chip. This
version uses a version of SCSI2 that isn't finalized, and this causes
incompatibility, mainly with certain tape and CDROM drives, but also with some
harddisks. This chip can in the A3000 be replaced with the "00-08" (or
sometimes also called "00-08 PROTO") chip, which contains true SCSI2. This
will also give the benefit of improved performance in some setups! GVP users
have a harder time, since GVP saw fit to surface mount the SCSI chip, and it
will require either a very skilled hand or special equipment to replace it.
Maxwell's problems with a SCSI2 drive might in this case lie more in the
specific SCSI implementation, either in software or hardware, in the A3000,
rather than depend on wether the H/A is SCSI1 or SCSI2. Replacing the SCSI
chip in the A3000 with the "00-08" version should cure all his problems. Also
worth mentioning: SCSI2 is fully downwards compatible with SCSI1, so nobody
don't worry about not being able to use new drives on old controllers.
Maxwell also has major gripes about ExpertPrep, and I understand him fully as
an Series2 A500-HD+ owner. I use Commodore's HDToolBox software instead of
GVPs unstable junk. It might not be able to set every parameter there is, but
in it's latest incarnations, it supports the most useful stuff, and it's
stable as a rock. HDToolBox has *never* screwed up on me, during my five years
as an Amiga harddisk owner. It will always warn you if you risk destroying any
data, so it's not neccessary to backup before changing basic stuff like
harddisk buffers, mask value or maxtransfer.
And by the way: to use HDToolBox with any of GVP's Series2 host adaptors, you
need to add the following tool type to HDTB's icon:
And that's it!
Finally, regarding the "to be or not to be" of an MMU in 'EC030 processors:
Yes, there *is* an MMU in many chips. However, it's often not working at all,
and will be disabled. But in fact, some batches of 'EC030 CPUs has been
delivered with fully working MMUs, because of short supply of "real" 'EC030
chips, some 'RC030 processors have been labelled as 'EC030. It should be
pointed out though, that it will be just by pure, dumb luck to have one of
these, fully functional MMU chips in your accelerator/A4000-030, do not count
Then again, many an happy 'EC030 owner has found out to have a partly working
MMU, that will in fact be able to catch some Enforcer hits, but not all, and
not able to run VMEM utilities, like GigaMEM. It's worth trying out with
Enforcer if you have an (albeit partly) working MMU, nothing will be destroyed
if you try. 8^) There's example programs that generates various types of hits,
and you'll be able to see which ones of them your MMU catches.
Now, do not take this as I think that everything Maxwell Daymon said in his
review is all crap and lies; that's not true. He did a really good job in his
test, and it's hard to write something as big as his review without making a
few mistakes. I have probably goofed myself somewhere above on these lines. If
that proves to be the case, feel free to tell me so!
Last, and not least: Thank You All at Amiga Report for devoting your time for
making this wonderful, wonderful magazine! It's always nice to snuggle up in
front of the screen with warm tea, chocolate chip cookies and a fresh issue of
AR! May the Haynie be with you forever, and never stop making AR! 8^)
- Thank you for the reply. I'd never envisioned a reader snuggling with
AR before. And considering that AR has survived into 3 editors now,
I think it has some staying power...
From: Fredrik_Lundin@p56.anet.bbs.bad.se (Fredrik Lundin)
Hi Jason !
First, I would like to comment on your leader about C= (AR#2.25).
I can understand why people worry if a new U.K "Commodore" wouldn't
give a damn about the USA, but remember... it's business.
Let's say Pleasance gets the Amiga, he must show his creditors that
he can make a profit on the Amiga, or they will dump it.
Why produce NTSC Amigas+US marketing when there's no Amiga friendly
_market_ over there, while back in the UK the Amiga is the leading
platform. (atleast for homecomputing and games)
Sure, it would be nice if they could, but it's probably to expensive.
So, I do really hope that CEI will get the license to produce the Amiga
in the US+Canada, so that the UK team can provide Europe with what we need.
I believe this is something YOU americans should push and really struggle
for (not only Americans of course), take contact with both CEI and the
UK team, make it happen...
- Well, nothing is finalized yet...and, of course, there's always the
argument about whether or not there's an Amiga market. It's there, it
just doesn't realize it yet. If Commodore, inept thought it was,
could produce machines for the world before, it's bound to be able to,
I have a problem with my CDTV. I attempted to upgrade my CDTV to 2.1 os
by installing developer roms(eproms) and a 2.04 rom. Well it didn't work-
I got nothing but a dark gray screen. if there was no CD in the machine
I wou;ld still get the CDTV logo but inserting any CD freezes the unit.
What can be up? BTW I have reinstalled the original eproms, rom and I still
have the no-op condition.
Any help *will* be appreciated.
- I passed this along to see if readers could help. Readers?
From: Roy Teale <email@example.com>
[This is a bit of a retrospective by Roy, but it's more of a testimonial
than anything, so this seemed a good enough place for it...-Ed]
Not too long ago it was said around my house that I had simply gone
mad - tipped over the edge by some simple complication that had
happened to me one day for no simple reason. I would shuffle around
the house muttering to myself and occasionally make a lunge for the
telephone to make a call to who-knows-where, followed by another
phone call to somewhere else, and finally settle back in my chair
and mope for a few hours before falling into a blue funk over . . .
well, nobody could understand unless they had a similar problem -
or a similar fate. I was an orphan, or so I felt. And I was the
darndest, most unlucky orphan I knew of. Mine was the fate of
being left behind in an industry which seemingly didn't care for
the unlucky end-user who happened to love their products.
I was on the verge of upgrading my Amiga 2500 to the much-needed Dos2.1
level, having forever been told that I should do so, because 1.3 was
just not that good anymore ... So, not wanting to invest in another
computer system just yet, (mind you, it would have to have been
another Amiga. I get enough of Pee-Cees in my electrical enginnering
department at the school I attend) I decided that upgrading my existing
computer was the most logical step to take. My A2500 was worth more
sitting on my desk than it would be getting sold to somebody else.
So gradually I had purchased the ECS chipset and installed everything
except for the 2.x rom. My problems started when I obtained that
rom. After that point, it was one swap after another (mostly
concerning my A2630 accelerator not being compatible with the 2.x
upgrade, and having to find a working set of eproms for that.) To
make an extremely long story very tight and tidy, I spend 5 months
of hair-pulling, long distance phone calls, talking to every
dealer I could find, sending my accelerator to various places,
and finally got it to work. To this day, nobody can give me the
correct story, but essentially it boils down to that particular
product (the A2630) not being supported by its parent company (C=)
anymore. Well, many changes have happened since I got the support
I needed (by Kasara Microsystems by the way), both to C= and to
my computer system.
I've purchased a Picasso II graphics board, a high-speed Zoom modem,
another hard disk, a nice 17" monitor, and AmigaDOS3.1. And it's
all plugged into my humble little A2500. I can't begin to describe
how much use I've gotten out of this system. Mostly it has to do with
the wonderful support I get over Internet. People, if you haven't
explored the Amiga areas in Internet, get a move on! Most of
my current setup, as far as software is concerned, has originated
from Internet downloads. To name a few, avm&Fax (a Great little
voice mail and fax package!!!), new Picasso drivers (which seem
to come out fairly regularly from Expert Services), On The Ball
(a calendar, scheduler, alarm clock, etc), numerous commodities
such as Yak, PowerSnap, MagicMenus. Also, one of the most obvious
additions to my system is Magic Workbench, a collection of icons
and backgrounds for the Workbench. <<May I put in a plug here for
supporting your Amiga developers if you are able. They have to
eat too, and I'd say that the $50 I paid Al Villarica for avm&Fax
is well-worth it. His technical support has been next-to-none,
and he's even made custom changes and bug-fixes for me, a day
after I talk to him about it.>>
I'm glad I stuck with my computer system through thick and thin.
The thin wasn't my computer's fault, nor do I wish to place blame
on anyone. These are simply hard times we're living in. But I'm
really happy with my Amiga system, and when I can afford it, I'll
probably upgrade to an A4000, or better, but for now I'll stick
with it. <<The only thing I need now is more memory (don't we all...)
You ever tried to do HUGE raytraces at the same time you're trying
to do a lot of other things? Memory tends to get eaten up rather
fast that way. A small commercial here: I've been hunting for a
DKB2632 expansion board for quite a while. That's the simm memory
board that fits piggy-back on the A2630 accellerator. They don't
appear to be making them anymore at DKB (maybe the plan on it in
the future, I don't know), and nobody wants to let go of them used,
so what's the deal here? :) Anyone want to sell me yours? Sorry,
I just had to do that.>>
So anyway, everyone has a story, and I'm sure everyone would like
to hear yours as well.
 Roy Teale  A2500 .. A2630 (28MHz 68030, 33MHz 68882, 4Mb) 
 Home: (509) 529-9971  A2091+2Mb .. 2-Meg Agnus Project .. AmigaDOS3.1
 Work: (509) 525-0055  Switch-Itt .. Zoom 14.4V Modem, Terminus, 
 Inet: firstname.lastname@example.org  AVM&Fax .. MicroWay FF .. Picasso II(2Mb) 
 finger for PGPpubkey  MAG MX17F Monitor ** Shopping for a DKB2632 **
From: "Donald H. Feldbruegge (608) 263-1497" <DH.FELDBRUEGGE@HOSP.WISC.EDU>
Dear Mr Compton & all the AR staff:
I just wanted to send a brief note to let you know that I enjoy Amiga
Report, ie that you do have a reader out here. I think that you are
doing a *great* job of keeping us Amigans informed about events and
happenings in our part of the world.
I first discovered AR about 6 months ago when I first got access, at
work, to the big world of the InterNet. After downloading AR the first
time, I found that it was very worthwhile and up-to-date; now I have to
check for AR the first thing on my weekly trips to the InterNet. I guess
that AR has become an even more important source of information with the
My uses of the Amiga are pretty tame, compared to many of you, so I'm
afraid that I truly don't have anything useful to contribute to AR or to
the Amiga community as a whole. I use my A2000 very much as home
computer. Word processing, a small PD spreadsheet, a small PD database,
my geanealogy program, and a bunch of games. I'm not especially good at
art/graphics or at music, and just don't have a lot of interest in Video,
so that makes me sort of a different Amiga user, I guess. I have had
experience with IBM and MAC at work, and I consider the Amiga *far*
superior to either of them. It is very powerful, and still remains easy
Again, thank you for AR. I like it and find it very useful. Now to
see if I can actually get this sent to you. I will have to copy this
note to an IBM-formatted disk using PC-task, then translate to the MAC I
use at work, before I can send it via an e-mail that I don't understand
very well at all. Best wishes to you and all the AR staff. Keep it up.
Don Feldbruegge (email@example.com)
- No problem. AR is, more and more, becoming an important part of the
Amiga community, and it pleases me to no end to see that.
Incidentally, there's no reason for anyone to be ashamed of not
being an Amiga power-user...I certainly don't push my 3000 to render,
spindle, and mangle graphics or blast out powerful original tunes...
AR pushes it to the limit and that's enough.