| T.R | Title | User | Personal
Name | Date | Lines |
|---|
| 1001.1 | Not really an answer | WJG::GUINEAU | W. John Guineau III | Wed Dec 23 1987 11:48 | 6 |
| 1001.2 | Not really slower | VTHRAX::KIP | | Wed Dec 23 1987 12:32 | 9 |
| Just wanted to clarify:
"not much faster" <> "slower"
What I was trying to point out was that the articles I've read indicate
that most of the hard drives available are only 2-3 times faster
than a floppy, which is very different from the PC hard disk world.
Can anyone else add anything about the RAM though?
|
| 1001.3 | ZZZZZZ | LEDS::ACCIARDI | | Wed Dec 23 1987 14:32 | 42 |
| Re: Floppy versus hard drive performance...
The Amiga floppies really aren't very slow; it's the file handling
system that's slow. Note that 256 KBytes of Kickstart code loads
in 17 seconds. This is about 15 KBytes/sec. What makes the floppies
slow is the continual gronking about the disk trying to find directory
entries and .info files. Unlike the ST and IBM formats, where all
directory entries are stored on a few consecutive tracks, the Amiga
scatters directory info all over the place, along with some redundant
info on how to rebuild the disk should you wipe aout a sector or
two. The win is that it's virtually impossible to permanantly kill
an Amiga floppy. The bummer is the incessant gronking.
I have a Supra 20 meg SCSI drive. The throughput is around 30-40
KBytes/sec. However, it can seek much faster than a floppy. As
a result, windows fill up with icons in a second or two.
The file handler portion of AmigaDOS is being re-written as we speak.
Supra has tested beta versions at over 250 KBytes/sec, which is
comparable to a fast AT drive.
Re: Zorro I and Zorro II...
Zorro I was the original spec for an expansion board for the A1000.
The specification defined an 86-pin architechture and a board physical
size, plus a bunch of other stuff I don't understand.
Zorro II defines a 100-pin buss and board design for the A2000.
Not many hardware manufactures built many Zorro I peripherals, and
it probably won't be supported forever. ASDG and Byte-by-Byte DID
support Zorro I, and you may be able to find some memory boards.
Zorro II is the way to go. I currently don't know of any Zorro
II expansion boxes for the A1000, although ASDG has promised one.
If your needs are for some extra memory and/or a hard drive for
the A1000, I'd recommend either a MicroBotics Starboard (holds 2
megs plus a SCSI board) or a Supra or C Ltd. combination SCSI
interface/RAM expander. All these products are neither Zorro I
or II compatible, but can fill your expansion needs.
Ed.
|
| 1001.4 | About Zorro II the gayer blade | 16BITS::KRUGER | | Thu Dec 24 1987 00:26 | 20 |
| Ditto .-1
Hard disk performance roars when compared to a floppy, and this
difference will be enhanced fairly soon with the release of the
new file system (whenever the C-A Gods So Decree).
About Zorro II -- one of the interesting differences between the
A-2000 and B-2000 is that the B-2000 has a much better protocol
for taking over the bus. That is, once the processor card takes
control, it becomes the master, and some other card can grab control.
Contrast this with the original design, where you grab the bus,
and are forever king of the hill until YOU release it (you being
a '020 of course). This approach is made possible by the awesome
integrated bus contention logic they have built into the B-2000.
I expect we will see the benefit in increased flexibility and nice
devices that do their own DMA but yet will listen when other devices
want their turn. Symmetrical Multiprocessing is coming! (Don't get
me wrong, it's a long way off....)
dov
|
| 1001.5 | Zorro I and Zorro II | TLE::RMEYERS | Randy Meyers | Mon Dec 28 1987 10:12 | 28 |
| Re: .3
> Zorro I was the original spec for an expansion board for the A1000.
> The specification defined an 86-pin architechture and a board physical
> size, plus a bunch of other stuff I don't understand.
>
> Zorro II defines a 100-pin buss and board design for the A2000.
Close, Ed. Both Zorro I and II are 100 pin boards. Except for a few
pins of interest to boards taking over the machine (like '020 cards),
they are electrically identical. The only difference is the physical
shape of the cards (square for Zorro I, rectangular for Zorro II).
It is even possible to plug almost any Zorro card into any Zorro slot
and have it work. The only problem you have is that you will not be able
to close the cover of the Zorro II box with a Zorro I card plugged in,
and you'll have to take a hacksaw to a Zorro I box to make room for
the Zorro II card.
The 86 pin boards were made by people who didn't wait for Amiga expansion
specs to come out from Commodore. They just took the 86 pin expansion bus
coming out of the Amiga 1000 (and now the 500) and extended and buffered
the wires. I think that there were only one or two companies who built
86 pin expansion cards and boxes.
Although, I think that occasionally people will refer to "slap-on-the-side"
products as 86 pin cards. Since Microbiotics has come out with their
Starboard to Zorro II adapter, their is some merit to thinking of the
S.O.T.S devices as 86 pin "cards."
|
| 1001.6 | | ELWOOD::PETERS | | Tue Dec 29 1987 17:52 | 11 |
|
Re: .3
Close, but there is one company selling a Zorro II box for the
A1000. CSA sells the turbo tower. It was designed for their
68020 processor, 32bit memory, scsi controller BUT they will
sell it alone. The box provides MORE slots than a Amiga 2000.
Steve Peters
|
| 1001.7 | 2 chip | ^2chip... | GLASS::SHIVES | | Tue Jan 26 1988 12:34 | 20 |
|
More about buying memory...
I am concidering buying a Starboard2 board. I would like to
go upto 2MB. When I called Abel Supply, I found out that they will
sell the 2MB board populated with either 0K or 512K. (Not 2MB)
My question is: is it better to buy the board populated or unpopulated?
How many chips will I have to buy for 2MB and what is the going
rate (I realize they are more volatile than the stock market).
Where is a good, reliable place to buy the chips?
Since I have never installed a chip before, are there any special
tools I should have and how likely is it I'll screw it up.
If there is not a SUBSTANTIAL savings I think I would rather buy
the board populated. But if I can save quite a bit, I will learn
to install chips.
Thanks, Mark
|
| 1001.8 | Use a SMALL hammer | WINNER::JBERNARD | John Bernard YWO/292-2591 | Tue Jan 26 1988 12:54 | 35 |
| It is usually quite a bit less expensive to populate the board
yourself. There are two companies that I know of that STOCK the
chips needed. ACTIVE Electronics in Westboro, Ma, and Calif. and
JAMECO Electronics in Calif.. 1 Meg (32 chips) from JAMECO is
approximately $100 and 1 Meg from ACTIVE is about $130. I have
done quite a bit of business with JAMECO and recommend them highly.
As far as special tools, etc. to install the chips; all you need
do is ensure you follow gooESD (i.e. static control) procedures.
Simply, make sure all power is off, make sure you ground yourself
(touch a ground, case, whatever) before unpacking and installing
the chips. Leave the chips in the bug mat (the conductive foam
the chips are shipped in) until you are ready to install them.
One of the best memory checks I have found is DigiView. I have
verified a memory problem by digitizing a black and then a white
plain piece of paper and look for dropouts on the screen. I saw
a couple white "specs", and ran a memory diag all night. In the
morning it showed 2 errors. I replaced the indicated chip and
the "specs" were gone on the next test digitize. Put the chip back
in and the specs reappeared.
Before you buy an unpopulated board, you might ask the manufacturer
if a memory test program is included. If it isn't, it can be a
bear to find a bad chip...
Byte-by-byte has a memory diag for their A500 memory. I don't know
what is available for other models.
Hope this helps...
-john-
|