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/// Usenet Repost:  Retina Vs. GVP Spectrum EGS 24-bit Video Boards
    ---------------------------------------------------------------
    By Kurt Haenen
    (haenen@cs.kuleuven.ac.be)



Hi there Amigoids,

I've  replaced my Retina 4MB board with an EGS 28/24 Spectrum with 1MB (It was
supposed  to  have  2MB, but there were some problems with the delivery) and I
want  to  share  my  opinion of both boards with you.  First of all :  I won't
compare  any  24bit  capabilities  at  the moment because it wouldn't be fair,
since I only had 1MB in the Spectrum, but lets talk about the rest.

The  Spectrum  sure has one thing my Retina didn't have :  good documentation.
Well,  that  is at first sight.  The docs clearly explain installing and using
the  software  that  comes  with  the  Spectrum,  ie.   the EGS system.  So, I
installed the stuff and tried it ...  At first it seemed to run fine, but then
...   FREEZE  ...  So, I reset my machine, start enforcer and what do we get ?
Yup, enforcer hits.

Enforcer Hit!  Bad Program!

18-Oct-93  01:02:40
BYTE-WRITE to  40059A3A        data=00         PC: 07B79F52 ----BUS ERROR----
USP:  07BB239E SR: 0004 SW: 00A1  (U0)(-)(-)  TCB: 07A04690
Data: 00000000 0000015B 00000166 00000000 10000000 000003FF 00059800 40059A3A
Addr: 40059A3A 07A09604 07BB23EA 07BB23EA 07B7F078 0793D44C 078007F8 --------
Stck: 07B71280 07BB23EA CE2C0132 07A09604 07A09604 021E015B 07B707E0 07976C02
Stck: 00000166 00000000 10000000 000003FF E1CF0046 036602BC 07BB74FC 07BB39FC
PC-8: 2C2B000C E08ECCBC 000000FF DC81DE34 6520063E 10876008 266F0004 10AB000F
PC *: 266F0004 246B0008 246A007C 47EA0114 598F2F48 001C3F41 001A2E8B 225345EF
Name: "Blanker Painter"

Enforcer Hit!  Bad Program!

18-Oct-93  01:04:54
LONG-READ from 4000D748                        PC: 00F82D28 ----BUS ERROR----
USP:  07B68A3A SR: 0000 SW: 1101  (U0)(-)(-)  TCB: 07B642C8
Data: 00001320 00000000 00000000 00000000 00000000 00000000 00000000 00000000
Addr: 4000D744 07AEBE20 00000000 00000000 00000000 00000000 00000000 --------
Stck: 00000011 00000000 0000000B 0000EA60 00000000 00000000 07A0270C 07A0270C
Stck: 07930898 07B69114 078007F8 00000000 0793CBEA 000207A0 270C0000 00000000
PC-8: 670412D8 53802209 08010000 66442200 C27C0003 2F017278 B081651A 48E73F3E
PC *: 4CD87CFE 48D17CFE 7230D3C1 9081B081 64EE4CDF 7CFCE488 67105380 22004840
Name: "EGS-ScreenMode"

These  are  just  some  examples of the Enforcer hits I get.  They all are BUS
ERRORS,  but  the  address  read  from  or  written to changes.  This is on an
A4000/040  with Zorro III on the Spectrum enabled.  I won't consider disabling
this,  cause  it's the only reason to have a Spectrum instead of a Picasso.  I
have  a  fat-buster revision 9, so this may be the problem, but it is not very
likely.   Since the board doesn't do DMA, the buster-bug should not affect it.
The  strange  thing is that there IS memory at that place (the graphics memory
of  the  Spectrum).   Has  anyone  else  experienced  this ?  Oh yeah, running
enforcer gives me a system that doesn't freeze up anymore, but everytime a bus
error  is  generated,  the  system  freeze  for a moment.  I send the enforcer
output  to  NIL:  so it isn't the printing of the output that causes this, but
the  bus  error  itself.  I also run the program that came with the board that
turns of the cache for the address-space of the card.

Before  you read on, I have to say that I have a 2 monitor system, so I do not
use the built-in display-switcher and I have told this to the install program.
One  thing  I  liked  about  my  Retina  was the way screens were handled, ie.
exactly  the  same  as standard Amiga screens.  Cycling through screens on the
Retina would also include standard Amiga screens, but on the Spectrum they are
completely  apart.   To  switch between Amiga and Spectrum screens you have to
use  a  hotkey, you can not simply press the screen-depth gadgets to get to an
Amiga  screen  if  the current one is a Spectrum screen.  And something really
anoying  is  that  when  your  using  the  standard  Amiga  modes  and use the
screen-depth  gadget  on  such a screen, the monitor has to resync even if the
underlying screen uses the same display mode.  Yet another software problem.

There  is  an  option to allow you to have a connection between the Amiga side
and  the  Spectrum  side, so that moving the mouse off a screen on one monitor
will  make  it  appear on the other one, but still it keeps blanking the Amiga
screen  when I move the mouse off it, so it isn't very useful.  Also the mouse
keeps  appearing  at  the wrong place when moving from the Amiga screen to the
Spectrum screen.  You move the mouse off the left edge of the Amiga screen, so
you  would  exspect it to appear at the right edge of the Spectrum, but NO, it
appears at the left edge :{(

The EGS system supplied catches your eye for a few moments.  Windows move with
their  entire  contents visible, you can put pictures in the background of the
screen,  have  a  24bit drawing in a window on top of that and simply drag the
window  and  its  contents in real-time.  This surely means the board is quite
fast  and  the supplied screen-blankers (especially scooter) only adds to this
impression,  *BUT*  if you have more than 1 screen on the Spectrum, the screen
cycling  (with  A-m  or the screen-depth gadget) is *SLOW* !  The Retina was a
lot faster at doing this and it think this board could do it a lot faster too,
so  my  guess  is that it's another glitch in the software.  To continue about
the  EGS  stuff:   it  really  sucks.  As I said, at first it looks great, but
then:  the clock always crashes, the display disappears (I mean the EGS screen
is  closed)  regularly,  simply  because there seems to be a small shortage of
memory  (I  have  8MB  fast-ram  and  still  it  isn't  happy)  and no serious
application  (I  mean  existing software) works under EGS.  I haven't found an
ADPro driver on my disks, so I couldn't use ADPro to display stuff and the EGS
viewer  can't  read  anything  else  than IFFs.  Once again I wanted my Retina
back.   It  may  have  been  a slower board, but the software was reliable and
useful.   It  didn't  crash  on  me  for  over 6 months. The Spectrum software
doesn't  crash  either (if we forget about the EGS stuff and only consider the
screenmodes), but there are a lot of things that aren't right:

  - To begin with: the enforcer hits.  This may be a hardware problem though.

  - When  using  CED 3.5 and opening a duplicate view (Amiga-d), the cursor is
    drawn  twice (in XOR I guess) in the newly opened view, so that is becomes
    invisible.   The  second cursor scrolls up and down together with the text
    and  only  disappears when you scroll enough to get it out of sight.  This
    problem  never  appeared  on the Retina or the Amiga native display, so it
    must be a bug in the Spectrum software.

  - As  stated  above, screen-shuffling is *SLOW*.  The Retina was at least 10
    times  faster  at  this than the Spectrum.  Since the Spectrum has a Zorro
    III  bus  and  the Retina only Zorro II, this should not be the case, so I
    guess  it's  again a software problem.  REMARK:  Could some Picasso owners
    tell  me  how fast the Picasso is in screen-shuffling.  I flip through the
    screens  a  lot  and I would like this to be snappy.  Also for the Picasso
    users:   Is  it  true that you can drag down screens on the Picasso to see
    the underlying screen ?  I heard this rumour ...

  - Powersnap  doesn't  work  anymore.  I do not know what exactly seems to be
    the  problem,  so  this could be a Powersnap bug, but it did not appear on
    the Retina.  Maybe it's because the screens are in fastram now.

  - There  are  no  programmers  docs  except  for the EGS stuff.  This really
    sucks.   I  am not going to write something for EGS.  Actually I hate EGS.
    All the nice commodities I have are useless on an EGS screen.  Oh well, my
    feelings  about  EGS  are probably not shared by others, so I won't bother
    you  with  them, but I really think they could have done a better job than
    this:   who the hell needs all those EGS gadgets and menus when you've got
    Amiga gadgets and menus *AND* MUI (which in my opinion are better).

No  promotion utility was provided with the Spectrum, but since I'm the author
of Promotor, that wasn't a big problem.

The  Spectrum of course has some advantages:  faster scrolling than the Retina
and  (silence)  ...   Well,  that's  about it.  The software of the Retina was
simply  a  lot  better  than the stuff for the Spectrum.  I have also used the
EGS-DisplayAdjust  program  to  get the most out of my monitor and yet again I
was  not  impressed.  The Spectrum can not achieve the same resolution/refresh
rate  my Retina could.  This seems quite odd, especially since all the talk in
comp.sys.amiga.graphics  indicated  that  the  max.  pixel speed of the Retina
should  be  lower  than  that  of  the  Spectrum.  I should state however that
according to the manual that came with my Retina, the Retina has a 90MHz pixel
speed,  not  75 as mentioned in all the comp.sys.amiga.graphics articles.  But
because  of  the  limitations  of  my  monitor  I  don't think the pixel speed
limitation  is  the  problem.   The real problem is the sprite.  My Retina did
800x600x8  bit at 86Hz on my monitor, the Spectrum can only go upto 83Hz, if I
push  it  higher, the sprite pointer gets screwed up if it's at the top of the
screen.   The  Retinas image also filled up my display nicely.  When using the
Spectrum,  even  when I turn my monitors knobs so that the display is as large
as  possible,  there  still  are  black  borders  to the left and right of the
screen.  I can remove those borders, but that means dropping the refresh rate
and  I don't wonna do that: I was just getting used to the rock-steady 86Hz.

Another problem with the Spectrum is the mouse-pointer:  the Retina had a nice
4-coloured (1 transparent) sprite for this, but the Spectrum seems to use some
weird  kind  of  sprite, with a kind of half-transparent color.  I do not like
this  !   Of course this is a question of taste.  Another anoying thing is the
image  the  sprite  uses:   I  work  on an A4000 and so I normally use a hires
sprite, but this seems to screw up the color information of the sprite used on
the  Spectrum.   Again a software problem.  REMARK:  Again, could some Picasso
II   users   tell   me   whether   or  not  the  Picasso  II  sprite  is  also
half-transparent.  Both cards use the Cirrus Logic chip-set, so my guess would
be  that  the Picasso also has this type of sprite, but I would really like to
know for sure.

Ok,  I'm  gonna wrap it up here ...  Conclusions:  I want my Retina back.  The
scrolling  was  slower, but the software was a lot better and it was *STABLE*.
Once again it has been proven to me that even the nicest board is shit without
decent  software.  Well, I guess that's about it.  I'll be giving the Spectrum
back to the store and will probably get a Picasso II (which seems to have much
better software) and a bit of money back.  Of course, due to the same chipset,
I guess the Picasso II will also have some of the problems (sprite and display
size)  I mentioned here, but at least you get a decent workbench emulation and
drivers  for ADPro and of course it's a lot cheaper than the Spectrum.  At the
moment  I  don't  think the Zorro III facility of the Spectrum is of much use:
under  normal  WB  operation, fast data transfer is only needed when scrolling
something.   And since both boards have a blitter to speed up this operation a
bit  (if  not  the  entire  area  needs to be refreshed), I don't think you'll
notice  the  additional speed of Zorro III a lot.  And then of course there is
the  fact  that  generally  German  firms have better software updates than US
companies.   I  know I'm gonna get flamed for this, but I really think this is
true.  GVP for example has an excellent record of supplying the user with neat
manuals,  but  I  haven't  heard  about  any software upgrade for any of their
products  (ok, maybe it's cause I'm in Europe).  MacroSystem for example has a
very  bad  record  concerning  manuals  (my  Retina came with some photocopied
stuff), but their software is continually updated and enhanced.  Ok, that's my
opinion, let the flamin' start :{)

One  last remark:  I think it's really outrageous that the graphics boards for
the Amiga cost so much money.  An EISA board with a Cirrus Logic chipset on it
(the  same  one  as in the Spectrum, Picasso and Piccolo) costs about $150 US,
while  the  Spectrum costs about $400 US.  For that kind of money a 80x86 user
gets  a  really fast Localbus S3 board which can do 1280x1024 in 24bit at 72Hz
non-laced.   With  the  bankrupcy (how does one write that) of C= being only a
small  step  away  (How  are  the CD32 sales in your country ?  How's the SEGA
promotion  campaign on your TV-station ?  Have you seen a single C= commercial
on  TV  ?   And  just  how many CD32 games have you seen ?  Didn't C= say that
there  were  going  to  be  17  games out by the time the CD32 was going to be
released  ?), maybe we should consider porting the Amiga look and feel to some
other platform.


                                          Hoping to get a better board soon,

                                          Kurt Haenen


Kurt  Haenen,  Student  Civil  Engineer,  Department  of  Computer Science, KU
Leuven.   (Where  you come from Civil Engineer may have a completely different
meaning.)

    Snailmail:    Homsemstraat 53, B-3891 Borlo, Belgium
    Email:        haenen@cs.kuleuven.ac.be  stud16@cc4.kuleuven.ac.be
                  fhgaa99@cc1.kuleuven.ac.be