Info-Atari16 Digest         Wed,  3 Apr 91       Volume 91 : Issue 189
 
Today's Topics:
                              _ (2 msgs)
                       Atari earnings (2 msgs)
               Can't connect a 1040st to a TV Set  :-(
                            Constructive?
            Graphics on the STE - v. generally speaking...
                       Hybrid Arts Sequencers?
                          MGR - What is it?
                                 Mice
                          Spectre 128 wanted
                 Telecom program help needed (2 msgs)
                   The cause of the phantom typist
 
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----------------------------------------------------------------------
 
Date: Thu, 4 Apr 91 03:47 GMT +1
From: ____ Zarko Berberski ____ <EBERBERS%yubgef51@pucc.PRINCETON.EDU>
Subject: _
To: Info-Atari16@naucse.cse.nau.edu
 
+---------------------------------------------------------------------+
|              if you feel this is not of general interest            |
| send answer to my address and I'll post summary as a single message |
+---------------------------------------------------------------------+
 
    Could any kind soul send me detailed description (or even better
a source code) of GIF,PCX,TIFF,IMG picture-formats and their creation.
I need to do GIF,PCX,TIFF <-> IMG conversion for a friend who will
very soon have to receive/store/retrive/"reformat"/send pictures in
all those formats. I'v choosen IMG format as a base since it seems to
be most widespread and easiest to manage but if GIF proves to be much
more space efficient then it might became the base. The key point is
that the whole proces will have to be done authomatically. Just to
make things worse ih has to be done while user (my friend) is on-line
and needs certain picture in a certain format and there is nobody home
to do it (except his ST, of course :-). So, there is no chance that any
paint program could be used for conversion and I'm very short with time
and information (yes I have GIF.DOC but have no time to reinvent the
wheel, although I usually like to do that :-).
 
<<<<<<<<<<<<--------<<>>-------->>>>>>>>>>>>
<<<<----      Zarko Berberski       ---->>>>
<<<<----  EBERBERS@YUBGEF51.bitnet  ---->>>>
<<<<<<<<<<<<--------<<>>-------->>>>>>>>>>>>
 
P.S.    Program like this can be a nice "Door" for a BBS so if anybody
      would like to have it let me know and I'll post it to the net.
 
------------------------------
 
Date: Thu, 4 Apr 91 03:52 GMT +1
From: ____ Zarko Berberski ____ <EBERBERS%yubgef51@pucc.PRINCETON.EDU>
Subject: _
To: Info-Atari16@naucse.cse.nau.edu
 
> I run STaTus BBS here in Auckland, New Zealand which is a multi line
> multi user bbs.  We run it under Michtron Version 3.0
 
    Have you by any chance heard of that anybody hava managed to use
Zmodem with Michtron V3.0 ?
 
>> We currently run two cd_roms the Atari cdar504's,
 
  WHERE DID YOU GET IT ??? For the last 12-24 months I'v been trying to
find any source of CDAR504-s here in Europe ! I would cetrainly like to
have so please let me know where it could be purchased from
(U.S, Europe ... ?).
 
<<<<<<<<<<<<--------<<>>-------->>>>>>>>>>>>
<<<<----      Zarko Berberski       ---->>>>
<<<<----  EBERBERS@YUBGEF51.bitnet  ---->>>>
<<<<<<<<<<<<--------<<>>-------->>>>>>>>>>>>
 
------------------------------
 
Date: 3 Apr 91 13:55:24 GMT
From:
 noao!ncar!elroy.jpl.nasa.gov!sdd.hp.com!spool.mu.edu!cs.umn.edu!thelake!steve@a
 rizona.edu (Steve Yelvington)
Subject: Atari earnings
To: Info-Atari16@naucse.cse.nau.edu
 
[In article <1991Mar11.222942.12560@chinet.chi.il.us>,
     saj@chinet.chi.il.us (Stephen Jacobs) writes ... ]
 
> Atari's results for the last quarter and the whole year were in the Wall
 Street
> Journal today.  They reported $0.15 a share earnings for the quarter on
> slightly lower than year-before sales.  All of this was due to an
 extraordinary
> credit for repurchase of debentures.
 
I saw a story on the Reuter business newswire that said Atari Corp. is
negotiating with Israel to establish a $150 million computer factory.
Israel is being asked to supply $100 million or so in loan guarantees
for Israeli component plants. Apparently if Atari assembles machines in
Israel using a sufficient level of Israeli-made components, the machines
can be shipped duty-free to the European Community. The production
capacity would replace plants currently operating in Taiwan.
 
----
  Steve Yelvington / P. O. Box 38 / Marine on St. Croix, MN 55047 USA
  INTERNET: steve@thelake.mn.org    UUCP: plains!umn-cs!thelake!steve
  GEnie: S.YELVINGTO2               Delphi: YELVINGTON
 
------------------------------
 
Date: 3 Apr 91 23:01:10 GMT
From: noao!ncar!elroy.jpl.nasa.gov!jato!vsnyder@arizona.edu (Van Snyder)
Subject: Atari earnings
To: Info-Atari16@naucse.cse.nau.edu
 
In article <A1055659651@thelake.mn.org> steve@thelake.mn.org (Steve Yelvington)
 writes:
>
>I saw a story on the Reuter business newswire that said Atari Corp. is
>negotiating with Israel to establish a $150 million computer factory.
>Israel is being asked to supply $100 million or so in loan guarantees
>for Israeli component plants. Apparently if Atari assembles machines in
>Israel using a sufficient level of Israeli-made components, the machines
>can be shipped duty-free to the European Community. The production
>capacity would replace plants currently operating in Taiwan.
 
Just the opposite of what USDOD indirectly did to Atari here:  When Inmos set
up their plant in Colorado springs to make transputers, which Atari would
have bought to put into ATWs, DOD wouldn't let Inmos re-export T-400's and
T-800's to UK, even though they were already being manufactured in UK!
 
--
vsnyder@jato.Jpl.Nasa.Gov
ames!elroy!jato!vsnyder
vsnyder@jato.uucp
 
------------------------------
 
Date: 3 Apr 91 20:26:14 GMT
From:
 noao!ncar!elroy.jpl.nasa.gov!swrinde!zaphod.mps.ohio-state.edu!pacific.mps.ohio
 -state.edu!ohstpy!miavx1!rlcollins@arizona.edu (Ryan 'Gozar' Collins)
Subject: Can't connect a 1040st to a TV Set  :-(
To: Info-Atari16@naucse.cse.nau.edu
 
In article <28735@fs2.NISC.SRI.COM>, todd@NISC.SRI.COM (Todd Koumrian) writes:
> It is too easy.  I also have an old 1040ST.  Not only is there no
> modulator board, but the composite output line that's supposed to come
> out the connector doesn't exist.  On later models it was added.  We're
> screwed.  My info comes both from the Atari ST Internals book and I
> asked at an atari shop just the other week about this.  Oh well.
 
Is there any spot on the motherboard to get the signal though?
 
------------------------------------------------------------------------------
Ryan 'Gozar' Collins      Question for MAC Users:      rlcollins@miavx1.BITNET
   ||||   Power Without    What IS the format of a     rc1dsanu@miamiu.BITNET
  / || \  The Price!!       MAC HFS floppy disk?       R.COLLINS1 on GEnie
------------------------------------------------------------------------------
 
------------------------------
 
Date: 3 Apr 91 23:29:01 GMT
From: o.gp.cs.cmu.edu!andrew.cmu.edu!mc4c+@pt.cs.cmu.edu (Mark Choi)
Subject: Constructive?
To: Info-Atari16@naucse.cse.nau.edu
 
You want constructive, TRH? Here it is.
 
You have power problems with external video? Well, since external video
would most likely only be used at a station that has wall power, why not
power the circuitry direct from the power line input. When there was not
power line input, ie, when you are using battery power, the circuitry is
off, and takes no power. Or the jack could act as a switch. When the
plug was in, then power would go tho this circuitry, other wise it would
not. This could work on either the monitor connection, thus allowing
battery powered operation for those who want it, or on the power jack.
When there is no external monitor connected, then it reverts back to the
original machine., so you have the best of both worlds. Battery life and
external video, or at least the choice.
 
The same thing can apply to the floppy. Put a switch on the drive that
allows it to power on when there is a disk inserted. Have a capacitor
set up so that on initial power on, it draws power from the capictors,
thus avoiding a spike in the power coming from the battery sort of like
an electronic fly-wheel. Also, while talking about floppy sensing, when
the heck will Atari connect the drive sense line, so that the cpu REALLY
knows when there is a disk inserted, and things like GCR can work
porperly. It would be great if the desktop could automatically update
windows when a new disk was inserted.
   Back to the notebook, why not include the battery powered drive
mentioned by TRH internally, and give an extra door on the bottom for
the seperate battery power for the floppy, if one is going to use it. I
prefer the above solution, but this is better than nothing.
 
As for the backlighting. No if's and's or but's. Not having a backlight
is a fatal mistake. I do not care how great the contrast is. Will it be
better than an active matrix display? Unless Atari has a new marvel in
LCD technology, I doubt it. Why did Apple have to redisign the mac
portable? Because of overwhelming complaints about the lack of a
backlight. Even with the incredible contrast of the active matrix
display on the mac, it was all but unusable in many conditions. Add a
stage light? By the time one finishes adding on all the things one needs
to use it, it will be just as huge as the STacy. Working in a lab with
diffuse overhead flouresent lighting will work fine. But for a machine
that is supposed to move around as much as a notebook, I do not think
that you can rely on good lighting being available. Innovative power?
How about this. Run a line from the hottest part of the circuit board up
to the corner of the display, probably the coolest, and use the heat
differential to create a current to power the backlight. I do not know
if the power will be enough, but it is an idea, anyway.
 
I also agree with whoever it was that said that external pointer device
support was essential. If I am and artist, I do not want to use an
iso-point type device to draw, or is the noebook not for artists? If I
am a musician, and am drawing waveforms for my dx-7 i do would rather
use a mouse. Or is this not for musicians? Actually, a mouse is useful
for just about everyone. I understand the space/power problems, but see
above for potential solutions, or try this one on for size. The mouse
connector could be modified to provide power TO the computer, and the
mouse would have it's own batteries. The mouse would power its own
controller, not the other way 'round. This could work on a redesigned
(simple) monitor connection as well. Also, why not design it so that the
LCD screen can open 180 degrees to the keyboard, and lock there, and can
also lock into any other angle as well, and use the touchscreen device
in the pad. Better for artist, musicians, and not that much more
intrusive that taking your hands off the keyboard to use the iso-point
like thingy. In fact I think it would be even better than the mouse, and
since such an input device is supposedly already running on the ST Pad,
the hardware is all but done. Add the handwriting recognition too, and
WOW!!! While you are at it, let the LCD seperate from the CPU/Keyboard,
and it would be incredible. You could set it up anywhere, just like a
monitor. Even hang it on the wall in front of your desk! :~)
   Yes, I am asking a lot, but am I asking too much? Think about it.
These things are very small hacks, of a mechanical nature (the seperable
locking LCD) and would be easy for any ID person. I will even do it! The
locking mechanism would double for the release mechanism that lets the
LCD separate. The cable coils into a slot in the cpu base. If great
distance is wanted, a longer cable will have to be bought, of course.
Third party people may even design an LCD connector To allow for this,
both ends of the connector must terminate in a plug. There is a small
easle, like on the back of a small picture frame, that allows the LCD to
stand on its own. Thus, you have a "seperable keyboard" setup, just like
the MEGA. Using a computer on your lap, even if it weighs next to
nothing, makes porblems like carpal tunnel syndrom look like a small
bruise. It is very difficult. The above set up alone would sell these
things to PC and Mac people like hotcakes to the famished. This machine
can be everything! And it would be a marketing dream if handled well. PC
ditto in ROM!!!! Yeah!
[How about adding foot pedals so that we can skip the batteries and
generate our own power :~)]
 
There are a lot of ideas that one can use to have one's cake, and eat a
large portion of it as well. I just do not see why it is absolutely
necessary to gut the machine to get more power. Why not try to get both
a full function machine, and more power? Don't tell me it is impossible.
When the mac notebook comes out, I'll prove you wrong! As it is, that
beast of a machine gets up to twelve hours of power. A smaller more
efficient machine.... We need to get the jump on the market, or else you
may find that the market has gotten away.
 Comments sugestions, post them wherever the hell you want. I'll read
'em, or I won't. Just like everyone else. Just quit a jumpin' down my
throat, especially those who do not know about what they are speaking.
I love you all.
 
                                                    Peace,
                                                    -geisha-
 
------------------------------
 
Date: 3 Apr 91 22:39:21 GMT
From: noao!ncar!elroy.jpl.nasa.gov!jato!hanauma.jpl.nasa.gov!hyc@arizona.edu
 (Howard Chu)
Subject: Graphics on the STE - v. generally speaking...
To: Info-Atari16@naucse.cse.nau.edu
 
In article <1991Apr3.055519.2322@ns.network.com> logajan@ns.network.com (John
 Logajan) writes:
>hyc@hanauma.jpl.nasa.gov (Howard Chu) writes:
>>Well, it's fairly simple to display a full 256-color GIF image, if that's
>>what you mean. I have code doing this in my port of Fractint 12. Using
>>frame-swapping to (almost) double the number of bits per pixel just about
>>squares the number of colors to choose from, and also squares the number
>>of colors displayable at once.
 
>I take it by frame swapping that you build two (or more) logical screens
>and alternate between them every vertical retrace -- so as to layer
>intensities on top of one another.  Thus your eye and the persistence
>of the phosphors become the brightness integrators.  A duty cycle kind
>of thing.  Let's see per color you have one frame-pixel full on and
>one frame-pixel in one of 8 possible levels.  Or one at level 6 and
>the other in 7 possible levels, etc .. 8+7+6+5+4+3+2+1=36 levels per
>color, or 46,656 possible colors to choose from.
 
Hm. I don't quite follow this description. Ok, assume one frame-pixel
full-on or full-off, =[0,7] (or [0,15] on the STe). Given equal display
time per frame (two frames) this extends the ST palette to an effective
12 bits, or 4096 colors. (Or extends the STe from 4096 to 32768.) Pretty
effective, and also surprisingly tolerable. I think this is what the
Colorburst 3000 program did. But, this is somewhat wasteful, because
this only uses 8 of the 16 available palette registers in the alternate
frame. (3 colors, full on or full off, 2**3=8.)
>
>Hmm, but you still only have 16 pallette cells to choose from per
>scan line, and you can only add them and not multiply them.  Giving you
>32 colors per scan line  (or scan zone in Spectrum 512 mode) max.
 
Well, as I mentioned above, you're not realizing the full potential
with the scheme you just outlined. Anyway, there are two alternatives,
and I've used both in Fractint. First, and most obvious - unbalance
the duty cycle. Use two alternating frames, but display one twice as
often as the other. This immediately makes all your pixel bits in
one frame "more significant" than the other frame. This gives you
color levels of 0-7 on one frame, and 0-2-4-6-8-10-12-14 on the other.
You now have 22 effective levels per color, or 10648 colors on an ST.
(STe - 46 levels, 97336 total colors.) But I think that's a little
extreme, it's also really just adding least-significant-bits, so all
you're really doing is gaining finer steps between color levels. Oh,
for the original poster, this means 22 and 46 gray-levels on ST and STe,
respectively, on a color monitor.
 
Now, as to adding and not multiplying colors... Consider these two
palette definitions... (Let's use octal, for readability, eh?)
 
Palette 0:      
                 020, 021, 022, 023, 024, 025, 026, 027
 
Palette 1:      
                 050, 150, 250, 350, 450, 550, 650, 750
 
By inspection you should be able to satisfy yourself that using these
two palettes on two evenly alternating frames, you will be able to use
8 bits per pixel and get 256 unique colors. Your maximum intensity is
reduced to half of what it used to be, but the brightness control will
fix that.  
decrease the red or blue resolution to suit your taste. This is what
you get on a PC with VGA, 3 bits for one color, 3 bits for another,
and 2 bits for the last. I don't recall what the 2-bit color on VGA is.
At any rate, it covers the full spectrum; there are no color gaps or
missing or overemphasized colors in this scheme.
 
[For med-rez, 16 colors, I used 
Note that now two colors are 1-bit each, and one color is 2-bits.]
 
I posted a small archive several months ago (cbox.arc) that demonstrated
this setup when I first got Fractint running. It draws 16 horizontal bands
on one screen and 16 vertical on another, then just toggles in the two
palettes on vertical blank. If you don't have this demo, you can write
it yourself based on the description I gave. It will take me at least a
week to get to my stuff if I have to repost it, as I no longer have an
accessible online copy and I still haven't settled into a place yet, so
my STuff is still in storage.
>
>My guess would be that flicker and pseudo-shadow movements would be
>quite severe. So how does it really look?
 
Try it and see, eh?  
entire 256 color palette of the PC w/VGA. Try other setups....
>
>--
>- John Logajan @ Network Systems; 7600 Boone Ave; Brooklyn Park, MN 55428
>- logajan@ns.network.com, 612-424-4888, Fax 612-424-2853
--
  -- Howard Chu @ Jet Propulsion Laboratory, Pasadena, CA
        Disclaimer: How would I know, I just got here!
 
------------------------------
 
Date: 2 Apr 91 21:31:30 GMT
From: hpcc05!hpcc01!wright@hplabs.hp.com (Jeff Wright)
Subject: Hybrid Arts Sequencers?
To: Info-Atari16@naucse.cse.nau.edu
 
Well, I was able to obtain enough information from Hybrid Arts to
convince me to place an order for "EditTrack Gold."  This product
is the successor to EditTrack II, and will be shipping at the end
of this week (if you believe software companies:-).
 
This product does not sound at all like the typical crippled entry
level sequencer (e.g., 60 track limit vs. 12 in Tiger Cub).  As far
as I can tell, the only thing that it lacks from the top end "SMPTE
Track" sequencer is the SMPTE support.  And the price is right -- $99
list, $75 when purchased direct from Hybrid Arts.
 
 
 
--Jeff Wright                           HP Circuit Technology R&D
  wright@hpctgrd.hp.com                   (HPtelnet/415) 857-5351
 
------------------------------
 
Date: 3 Apr 91 22:18:11 GMT
From: ucla-seas!boole!plinio@locus.ucla.edu (Plinio Barbeito)
Subject: MGR - What is it?
To: Info-Atari16@naucse.cse.nau.edu
 
In article <533@uqcspe.cs.uq.oz.au> warwick@cs.uq.oz.au writes:
>I've noticed MGR on atari.archive in the MiNT directory.
>
>What is it?
A window manager -- a program similar to X that allows you to run
different programs concurrently while showing the output of each
program in a separate window.  You can interact with each program
by clicking in its window.  You can 'iconify' a window so that it
gets out of your way and appears as a small icon on the screen.
MGR allows you to select a different font for each window containing
text.  Each window has a mercifully small border that saves valuable
space on the screen (as opposed to GEM).
 
Thus, a typical scenario is that you'll have a clock running in a corner
of the display, you can be typing in an 80x25 shell window, have a download
going in an inverted white-on-black smaller window, etc...
 
>Do I need to be running MiNT to use it?
Yes, you need to be running MiNT for the multitasking support, and you'll
need to have more than 1 Meg of RAM to get started.  To be comfortable, I
suppose maybe 3 Megs would do it, but I have been getting by with 2.
You'll also want a mono monitor, the bigger the better.  Hard disk?
Yes, MGR comes with a lot of programs, font files, etc.  It would
probably not be worth the trouble (or impossible) to use it off of
floppies.
 
Thanks to T R Hall for posting the solution to the 4 Meg memory limit
problem.  We are going to need those 16 Megs, whether we get them in ST
memory or SST or TT memory.
 
plin
--
----- ---- --- -- ------ ---- --- -- - -  -  plinio@seas.ucla.edu
This page intentionally left blank so that it could contradict itself.
 
------------------------------
 
Date: 3 Apr 91 22:15:47 GMT
From: o.gp.cs.cmu.edu!andrew.cmu.edu!mc4c+@pt.cs.cmu.edu (Mark Choi)
Subject: Mice
To: Info-Atari16@naucse.cse.nau.edu
 
Opto-mechanical means that a light beam passes through slits in a wheel
that spins as the mouse moves, one horizontal, and one vertical. a light
sensor on the other end senses the light pulses and converts these to
movement info for the mouse controller. There is a rubber ball with
little spikes all over it that is used to clean mice. Just place it in
the chamber, and run the mouse around for as few seconds. It is for the
mac, and I do not know if there is one with a bigger ball for the ST. A
great idea, though.
                    -geisha-
 
------------------------------
 
Date: 3 Apr 91 22:05:32 GMT
From: mimsy.umd.edu!cwilliam@mimsy.umd.edu (Christopher Williamson)
Subject: Spectre 128 wanted
To: Info-Atari16@naucse.cse.nau.edu
 
I am looking for the old Spectre 128 cartridge with or without ROMs
for the Atari ST.
 
I may also be interested in a GCR, but the 128 is all I really need.
 
If you have an old 128 lying around from when you upgraded to GCR, let
me know, Ill buy it!
 
Chris
 /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
 
  Christopher Williamson | cwilliam@cs.umd.edu             | InterNet
  HCIL, 4166 AVW Bldg    | merlin (tumtum.cs.umd.edu 2000) | Goth MUD
  Univ. of Maryland      |...!uunet!mimsy!cwilliam         | UUCP
  College Pk, MD 20742   | (301)405-2725W / 595-7942H      | If all else fails
 
    " Horses are born trying to kill themselves.
          The best we can do is make it difficult for them... "
 
------------------------------
 
Date: 3 Apr 91 22:05:29 GMT
From:
 noao!ncar!gatech!udel!wuarchive!zaphod.mps.ohio-state.edu!lavaca.uh.edu!menudo.
 uh.edu!rcte2p@arizona.edu (Paul S. Sears)
Subject: Telecom program help needed
To: Info-Atari16@naucse.cse.nau.edu
 
ekrimen@ecst.csuchico.edu (Ed Krimen) boldy writes in article
 <1991Apr03.184303.19277@ecst.csuchico.edu>
>In article <1991Apr3.170133.2948@menudo.uh.edu> rcte2p@menudo.uh.edu (Paul S.
 Sears) writes:
>>>
>>>Why not try RUFUS, it is in German and is Shareware,
>>
>>Can someone d/l it from Genie and post in on atari.archive?  I assume
>>that it is PD...  I no longer have a Genie account to do this...
>
>It's already on atari.archive.
>
 
Ok.  It is.  I never saw it before... Been on there since November.
Anyway, I am using it right now, but, one comlaint is that it is not a
speed demon :-).   Uniterm is still one of the fastest fully vt100
compatible emulators out.  I do like being able to change fonts in
Rufus.  However, I don't know any German so I am lost on its features.
 
BTW, I saw that uniterm.tar.Z was dated April 3 (today!) - is this a new
version? or did someone just re-upload it?
 
(Anyone want to try to do a emulator in assembly and still keep it fully
vt100?)
 
Later!
 
--
Paul Sears      The Univ. of Houston |"The greater an individual's power
Student of the College of Technology | over others, the greater the evil that
RCTE2P@Jetson.uh.edu      ***        | might possibly originate with him."
RCTE2P@menudo.uh.edu     * * *       | - PROPAGANDA, from A Secret Wish (CD)
 
------------------------------
 
Date: 3 Apr 91 23:10:21 GMT
From:
 noao!ncar!elroy.jpl.nasa.gov!usc!chaph.usc.edu!aludra.usc.edu!hk@arizona.edu
 (knuyh)
Subject: Telecom program help needed
To: Info-Atari16@naucse.cse.nau.edu
 
   Could somebody post/send me how can I convert SF314 3.5 drive to
   dobule side drive?
 
   Thanks.
 
------------------------------
 
Date: 3 Apr 91 18:46:36 GMT
From:
 noao!ncar!elroy.jpl.nasa.gov!sdd.hp.com!spool.mu.edu!snorkelwacker.mit.edu!bloo
 m-beacon!eru!hagbard!sunic!dkuug!imada!micro@arizona.edu (Klaus Pedersen)
Subject: The cause of the phantom typist
To: Info-Atari16@naucse.cse.nau.edu
 
jan@janhh.hanse.de (Jan Willamowius) writes:
 
> struct 
>   ..
>   struct tRec /* application recording as described in Appl_tRecord() */
>   
>   long   t_how;     /* arguments */
>   
>   ..
> 
 
>>   void /* enqueue input for forker */
>> forkq( void(* who)(), long how)
>> 
>>   extern fpcnt, fpt; /* fork-pipe-tail index */
>>   if( fpcnt < 32)
>>   
>>     if( fpt == 32) fpt= 0;
>>     rec->t_who= who;
>>     rec->t_how= how;
>>     fpcnt++;
>> 
> (copyright by Digital Research Inc, 1985, April 15 (!))
> What happens if forkq() is called non-interrupt, the fpt index is at 31 and
> the code gets reentered (interrupted) between fpt++ and if( fpt == 32) ..?
 
You might be right there...
 
> To exorcise one may
> 1) Replace expressions like ++i; if(i == ANYPOWEROFTWO) i= 0;
>    by ++i &= (ANYPOWEROFTWO - 1)
 
????? in what language do you want to write that ?????
 
What you are writing is :
    ++i = ++i & (APO2-1);
 - no matter how you try to hide it...
 
But ok, I understand what you mean - what you want is a interlocked add cyclic.
  IAC 1,APO2,i  - but no compiler can generate that to a 68K. Some
signal processors can (and they are not restricted to powers of 2 (Analog
Devices).
 
 
> 2) make sure the interrupts are disabled whenever forkq() is called
>    (from chkkbd(), mchange() and ap_tplay())
 
This is a lot easier than making a new CPU with new instructions and a new
C-like compiler that can generate them...
 
> 3) recompile, assemble and link the system.
 
might be hard to do with '1)'...
 
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Klaus  (micro@imada.dk)
 
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End of Info-Atari16 Digest
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