rlcarr@athena.mit.edu (the Wizard of Speed and Time) (01/13/90)
I have almost decided to buy either an A2620 or A2630 accelerator board.
My current setup:
A2000 w/Super Agnus and 1 meg chip RAM
4 meg of fast RAM
HardFrame/2000 SCSI controller
(1) Will the A2620 allow you to boot off the 68000? What about the A2630?
(2) Can KickStart ROM be copied to the 32 bit ram on the A2620? What about
the A2630?
(3) How much faster (overall, graphics, hard drive I/O,
and math grinding) is the A2620 compared to my A2000? How about
the A2630 compared to my A2000? The A2630 compared to the A2620?
(4) What kind of RAM does the A2620 use? The A2630? How hard is it to find?
How hard to install?
(5) If I someday ever want to run Amiga UNIX, can I run it with an A2620?
How about with an A2630 (assuming I get a big enough hard drive,of course)?
(6) Can I put hard drive buffers in 32bit ram? Right now I can put hard drive
buffers in my fast ram.
(7) Does the 32bit RAM autoconfig?
(8) will the A2620 be able to access my 4 meg of fast ram? What about
the A2630?
(10) is there any way to force a program to be placed in 32 bit RAM?
can you force a program into 16 bit RAM?
That's all for now - but if you can think of other information, please
pass that along too.
Thanks!
--
Rich Carreiro - Most Biased Boston Celtics Fan! "So long, farewell, and may
ARPA: rlcarr@space.mit.edu the forces of evil become
UUCP: ...!mit-eddie!space.mit.edu!rlcarr confused on the way to your
BITNET: rlcarr@space.mit.edu door!" - George Carlinbillsey@agora.UUCP (Bill Seymour) (01/14/90)
In article <1990Jan12.222613.28109@athena.mit.edu: rlcarr@space.mit.edu (the Wizard of Speed and Time) writes:
:I have almost decided to buy either an A2620 or A2630 accelerator board.
:My current setup:
:A2000 w/Super Agnus and 1 meg chip RAM
:4 meg of fast RAM
:HardFrame/2000 SCSI controller
:
:(1) Will the A2620 allow you to boot off the 68000? What about the A2630?
Yes on both counts.
:(2) Can KickStart ROM be copied to the 32 bit ram on the A2620? What about
: the A2630?
Again yes on both. Use SetCPU FASTROM.
:(3) How much faster (overall, graphics, hard drive I/O,
: and math grinding) is the A2620 compared to my A2000? How about
: the A2630 compared to my A2000? The A2630 compared to the A2620?
I don't have a 2620, but the most accurate speed test I have (Speed,
by Jez San or Argonaut Software) shows me at 6 times the speed of a 1000
and 2 times the speed of a 2620. My HDs now all run at the fastest I'd
expect them to... ~600K/sec with RLL and ~400K/sec with MFM. Note I have
a Supra Wordsync nonDMA controller, so your speed *will* vary from mine.
:(4) What kind of RAM does the A2620 use? The A2630? How hard is it to find?
: How hard to install?
They both use 256Kx4 ZIPs at 100ns. Pretty easy to find and not too
expensive. (You should be able to find them for less than $15 each.)
:(5) If I someday ever want to run Amiga UNIX, can I run it with an A2620?
: How about with an A2630 (assuming I get a big enough hard drive,of course)?
Don't know here for sure, but the first beta AMIX machines were used
with 2620s. The release might require a 2630. I know it currently requires
C=s HD controller and a tape drive.
:(6) Can I put hard drive buffers in 32bit ram? Right now I can put hard drive
: buffers in my fast ram.
Youu should be able to.
:(7) Does the 32bit RAM autoconfig?
Yes. The 2630 also has a RAM expansion buss for piggybacked ram
boards. My guess is that boards built for this buss will not be autoconfig.
But, you can put 64 meg of ram on it!
:(8) will the A2620 be able to access my 4 meg of fast ram? What about
: the A2630?
Yes to both.
:(10) is there any way to force a program to be placed in 32 bit RAM?
: can you force a program into 16 bit RAM?
I believe there's a PD utility for individually setting memory
priority for each bank of memory on the system. Kind of a super FastMemFirst.
Judicious use of that would allow youto choose where pretty much anything goes.
:That's all for now - but if you can think of other information, please
:pass that along too.
All I can add is that I *like* my 2630! Things are a joy once more!
:Thanks!
:
:--
:Rich Carreiro - Most Biased Boston Celtics Fan! "So long, farewell, and may
:ARPA: rlcarr@space.mit.edu the forces of evil become
:UUCP: ...!mit-eddie!space.mit.edu!rlcarr confused on the way to your
:BITNET: rlcarr@space.mit.edu door!" - George Carlin
--
-Bill Seymour ...tektronix!reed!percival!agora!billsey
=============================================================================
Bejed, Inc. NES, Inc. Northwest Amiga Group At Home Sometimes
(503) 281-8153 (503) 246-9311 (503) 656-7393 BBS (503) 640-0842a464@mindlink.UUCP (Bruce Dawson) (01/14/90)
To Bill Seymour's comments on the 2620/30 I would like to add one
comment. If you have old (16-bit) fast memory and you buy a co-processor
board, the correct thing to do with your old fast memory is to remove it from
your Amiga. Throw it out, sell it, anything. If you don't, then everytime you
access that memory, your expensive coprocessor board will slow down virtually
to the speed of a 7.16Mhz 68000. What a waste! If you need the extra memory
(and you may well, if you were used to using all of 3-megs, you should probably
expect to upgrade to 5-megs for the '020/'030 because of things like kickstart
in RAM, bigger disk buffers so the disks can keep up to the processor etc.)
then you should sell your old memory board and buy extra ram for your
coprocessor. Your system will run much faster and you will probably make money
on the deal.
Oh yeah, one other thing. If you haven't already, get a fat-agnus,
because otherwise you will have some _really_ slow memory in your memory list.
Also, while on the topic of memory speeds, I would like to clear up some
misinformation which was tossed around recently.
The standard Amiga 68000 cycles last 140ns. However, a 68000 takes four
cycles to read or write memory (minimum) so that it actually takes 560ns to
read or write anything. Half of this time is spent on the bus, and during the
other half, other chips (display chips for instance) can read from the memory.
Some memory boards may have wait states, but I'm not aware of any (for the
68000 anyway). After all, it doesn't take very fast memory to run no
wait-states at 7Mhz, when it takes four cycles for a read. 150ns memory should
work just fine. If there are wait states, then the time will increase to 700ns
(assuming one wait state). Many 68000 instructions execution times are
determined by the time required to read the instruction. Some take slightly
longer, and some, such as multiply (38-70 cycles, plus <ea> time) take far
longer. Read the manuals for details. The '020 can do three cycle reads, the
'030 can do two cycle reads and the '040 can (so I hear) do one cycle reads.
Personally, I'm holding out for an '050 that does zero cycle reads :-)
So, a stock Amiga can execute a _maximum_ of 7.159/4 million instructions
per second or 1.79 million instructions per second.
.Bruce Dawson.daveh@cbmvax.commodore.com (Dave Haynie) (01/16/90)
in article <1990Jan12.222613.28109@athena.mit.edu>, rlcarr@athena.mit.edu (the Wizard of Speed and Time) says: > Summary: any problems? > Xref: cbmvax comp.sys.amiga.tech:9947 comp.sys.amiga:49795 > (1) Will the A2620 allow you to boot off the 68000? What about the A2630? Yes. Yes. Both give you a menu if you reboot the system while holding down both mouse buttons. > (2) Can KickStart ROM be copied to the 32 bit ram on the A2620? What about > the A2630? Yes. Yes. > (3) How much faster (overall, graphics, hard drive I/O, > and math grinding) is the A2620 compared to my A2000? How about > the A2630 compared to my A2000? The A2630 compared to the A2620? With a FASTROM in place, your overall system speedup is roughly 4x with an A2620, 8x with an A2630, but it does vary depending on what you're doing. Any floating point intensive applications that offer FPU coded versions may run 25x-50x faster than on a stock 2000. Both integer and floating point stuff on the A2630 is about twice the speed of the A2620 (FPU stuff would be a bit better than this is the program is written with the 68882 in mind). > (4) What kind of RAM does the A2620 use? The A2630? How hard is it to find? > How hard to install? They both use 256k x 4, 100ns, ZIP package, 414256 or similar DRAM. I've never had to find it on my own; it's a solder-in job, not too difficult for anyone with reasonable soldering experience, but not what I'd call a beginner's job. > (5) If I someday ever want to run Amiga UNIX, can I run it with an A2620? > How about with an A2630 (assuming I get a big enough hard drive,of course)? With enough memory and hard disk space, it's supposed to run on both. I suppose the UNIX people will have a list of requirements or some such when appropriate, but the basic requirement is certainly the 32 bit CPU + MMU. > (6) Can I put hard drive buffers in 32bit ram? (7) Does the 32bit RAM autoconfig? Yup, the 32 bit RAM can be accessed by DMA, and it autoconfigures. > (8) will the A2620 be able to access my 4 meg of fast ram? What about > the A2630? They both use the first 2 or 4 megs of autoconfiguration space for their 32 bit memory, leaving 4 megs of space for more memory, bridge card, whatever. If all you have is 4 megs of 16 bit memory, that's no problem. > (10) is there any way to force a program to be placed in 32 bit RAM? > can you force a program into 16 bit RAM? The OS doesn't really differentiate. The 32 bit memory will be first in the memory lists, based on how autoconfig currently does things, and as such it's the first to get used. Some RAM disks automatically allocate from the end of memory, and would get 16 bit memory in such a system. This is just the way things happen to work, though, nothing's forcing the issue. > Rich Carreiro - Most Biased Boston Celtics Fan! "So long, farewell, and may -- Dave Haynie Commodore-Amiga (Systems Engineering) "The Crew That Never Rests" {uunet|pyramid|rutgers}!cbmvax!daveh PLINK: hazy BIX: hazy Too much of everything is just enough