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APPLE II DEVELOPMENT FORUM CONFERENCE LOG
Tuesday, May 15, 1990  10:00 p.m. eastern time
Topic:          Beginners Night         
Special Guest:  Ron Lichty  (Co-author of the book "Programming the
                             Apple IIGS in Assembly Language"
Forum Leader:   Dave Sugar  (AFL Dyfet)


AFL Dyfet  Okay, everyone, good evening and welcome to the Apple II
AFL Dyfet  Development Conference (Excellant work, Parik!).  Tonight is
           beginners
AFL Dyfet  night here.  This is an opertunity for those new to programming
           to
AFL Dyfet  get expert advice.  I would like to start tonights conference by
           turning over
AFL Dyfet  the floor briefly to Ron Lichty, Co-author of "Programming the
           Apple IIgs in
AFL Dyfet  Assembly Language", who has an announcement to make...Ga Ron...
RonLichty  Thanks, David.
RonLichty  As you know, Programming the Apple IIGS in Assembly Language has
           been
RonLichty  called "a must for would-be Apple IIGS programmers".
RonLichty  Using the APW or ORCA/M assembler, the reader develops,
RonLichty  in stages a Hello, World program -- from an 8-line program
RonLichty  that prints on the text screen to a full-blown desktop application
           with
RonLichty  menu bar, dialogs, icons, and multiple, sizeable, scrollable
           windows.  
RonLichty  Plus it includes the reference section from our earlier book
RonLichty  that everyone likes so much.
RonLichty  And we've had a disk out in APW and ORCA/M assembly all along.
RonLichty  Cecil Fretwell announced here a few weeks ago
RonLichty  that he had converted Hello, World into C for both
RonLichty  APW and ORCA versions of C.
RonLichty  His disk contains a cross-reference file that line-numbers the
           entire final
RonLichty  C csource code and cross-references its functions and variables
RonLichty  in addition to providing source and compiles at all the points
RonLichty  the other disk does.
RonLichty  Now Ken Kashmarek, author of SoftSwitch, has translated Hello,
           World
RonLichty  for Merlin 16+ assembler.  The result is two different versions of
           the
RonLichty  final program to compare.  Ken converted the first version by
           hand,
RonLichty  line by line, from the book; he used the new Merlin supermacros,
RonLichty  which whorten the source file considerably, and added a couple
           inline macros
RonLichty  to make the programming easier, but left off the comment lines.
RonLichty  He created the second by running the Merlin 16+ Converter routine
           on the
RonLichty  original program listing, so it includes all comment lines,
RonLichty  but does not use the supermacros.
RonLichty  Anyway, all are available from me by mail.
RonLichty  If you can't find the book in a bookstore, it is too.
RonLichty  The book: $32; APW/ORCA/M disk $20; C disk $20; Merlin disk $10.
RonLichty  From Ron Lichty, P.O. Box 27262, San Francisco, CA 94127
RonLichty  (U.S. funds only, and CA tax for CA residents please).
RonLichty  Also, there's an errata
RonLichty  of the two bugs, the error in the text, and the olne serious typo
           that
RonLichty  have been found in the book just by sending a self-addressed,
           stamped
RonLichty  envelope to the same address.
RonLichty  Whew.
RonLichty  ga
RonLichty  Oh, can I add
RonLichty  for those who don't know, that I've returned to engineering
RonLichty  from product marketing -- I'm working on the Apple IIGS Finder
RonLichty  at Apple these days.  ga
AFA Parik  ()()()()()()()()()() *yipee*!!!
A2GS       Yay!!
AFL Dyfet  Thank you, Ron...that is a long brief intro :)...Go ahead
           Parik...
AFA Parik  real quickly; how did you determine the # of cycles in your 1st
           65816 book ron?
AFA Parik  for each opcode that is.  ga
RonLichty  Let me think back that far...
A2GS       He used a stopwatch naturally.   :)
RonLichty  We had several sources, most of them wrong in at least some
           areas.
RonLichty  We had the data sheet from Western Design,
RonLichty  a set of by-addressing-mode cycle descriptions from Western
           Design,
RonLichty  a similar kind of look from insiders at Apple,
RonLichty  a reference card from GTE (different errors from the Western
           Design ones)
RonLichty  and I think at least one other source.
AFA Parik  ok.  just checking if logic analyzer was used.  thanks!  ga
           (done)
RonLichty  We did not have any way, ourselves, to prove one thing or
           another,
RonLichty  if I remember correctly,
RonLichty  but just puzzled out all the data until it made sense.
RonLichty  ga
AFL Dyfet  Go ahead A2...
A2GS       Are the correct cycle timings available from WD?
RonLichty  I would use the ones from our book.
RonLichty  As far as I know, we got them all right.
RonLichty  ga
RonLichty  Thanks.
AFA Parik  what is the picture on your 1st book?  the motherboard?
RonLichty  That's the mask of the chip itself.
RonLichty  I have one blown up to poster size.
RonLichty  It's really beautiful.
RonLichty  When Hayden
RonLichty  was publishing ORCA/M assembler, they did full-color
RonLichty  separations and printed the posters.  ga
AFL Dyfet  Go ahead Scott...
AFL Scott  How do you like being back in Engineering?
RonLichty  It was really hard, at first.  I had to get used to 
RonLichty  not earning a living talking to people, both online and on the
           phone!
RonLichty  And the Finder code is, as you might imagine, a bit complex.
RonLichty  But I have always liked solving a good problem, so I'm happy. 
           ga
AFL Dyfet  (an honest living, Engineering :)... Go ahead, Wind...
AFL Dyfet  While we're waiting on Windrider, Go ahead Floyd....
AFL Floyd  Hi, Ron.  I don't know if you are aware of it or not, but there
           are a few
AFL Floyd  Finder patches floating around that allow folders on the desktop
           and allow
AFL Floyd  the default quit dialog to be changed.  I hope you and Jim and the
           other
AFL Floyd  Finder gurus consider changing the Finder to allow stuff like
           this. ga
RonLichty  I've seen several patches.  But would like to see the ones
RonLichty  you've just listed--don't think I've seen those.
Michael515 Are the patches in AUT Floyd?
RonLichty  We're always looking to our users for input on how we can
           improve
RonLichty  things.  
AFL Floyd  Look in the "IIGS Utilities/Finder Patches" topic of the Utilties
           forum,
AFL Floyd  keyword AUT. (blatant plug) ;)
AFL Floyd  Oh, one more thing...put back "Remove" in the menu for quick
           deleting. ;)
AFL Floyd  ga
RonLichty  Thanks for the information on that.
RonLichty  What if "Remove" moved the file to the trash instead of deleting
           it?
AFL Floyd  That is even better, Ron! ga
AFL Dyfet  Go ahead, Windrider...
Windrider5 I have been programming the IIgs using C for a couple of years
Windrider5 Do you think it is worth it to learn assembly language?
RonLichty  Should you learn assembly?  Well,
RonLichty  that really depends on what you want to get out of programming.
RonLichty  I like assembly because it lets me get right down into the
           processor
RonLichty  and listen to the gates open and close.
AFA Gary J :)
RonLichty  When I write in assembly, I know exactly what's going on with the
           machine.
RonLichty  And my code is a lot shorter and a lot faster.
RonLichty  It takes longer to write than C, though given C's propensity
RonLichty  for null pointers and it's write-only nature,
RonLichty  I'm not sure assembly is a lot more dangerous than C to write
           in.
RonLichty  You can certainly do things like floating point a lot easier in
           C.
Windrider5 write-only nature?
RonLichty  I personally didn't find learning assembly hard.
RonLichty  I do get annoyed by the addressing modes that show up only
RonLichty  with certain instructions.
Coach101   Amen!
RonLichty  But the 65816 is a kludge built on the kludge of the 6502 :)
RonLichty  And I think there are a lot of us who find its quirks rather
           winning!
AFL Dyfet  On the other hand, it's more balanced than the 8086 instruction
           set :)
RonLichty  By C's write-only nature, I mean
RonLichty  that while C is easy to write because you type so few
           characters,
Dave Lyons <-- doesn't find C particularly write-only
RonLichty  reading the code you wrote last week in C can be as hard as
           reading
RonLichty  assembly you wrote last week.  Especially if you do what many
RonLichty  good programmers do and succumb to the clarion call of terseness
RonLichty  that C offers.  I think it may be possible to write an entire
           program
RonLichty  in a single C statement.  And all too many C programmers try to do
           it!
RonLichty  Let me add that I agree with you, David, that
RonLichty  I'd much rather have a 65xx processor than an 8086 family
           processor.
RonLichty  I've written code generators for compilers for both.
RonLichty  The 8086, with its banks built on 16-byte boundaries, is an ugly
           kludge
RonLichty  (as opposed to the 6502, which (I suspect entirely by chance)
           turned
RonLichty  out to be a nice kludge).
A2GS       Somewhat similar to the drawbacks on the 68000!
RonLichty  Also, have you ever tried to decipher the structure of
RonLichty  opcodes on the 8086?
AFL Dyfet  :)
RonLichty  They are based on two bits here and three bits there and
AFL Dyfet  Up to 7 byte sequences :)
RonLichty  prebytes and post bytes and...  Yuck!!!!!
RonLichty  ga
AFL Dyfet  Okay, Go ahead Coach...
Coach101   As to learning assembly,
Coach101   Unless you are into writing device drivers or some other, rather
           internal, parts of the IIgs
Coach101   environment, you can do everything from C (and with Orca-C, no
           little interface glue in assembler)
Coach101   So, you will learn a lot about how machines really work by writing
           in assembler, but it is not
Coach101   required in order to write most things for this system.  As to
           "Write Only C"...
Coach101   Ron, I think it is not the language but the programmer.  The same
           terseness and lack of comments will 
Coach101   render an assembly program even more unreadable.  My personal
           hatred is the race to see how much
Coach101   code (as opposed to loop control) a C programmer can kram into a
           "for" statement....  On processors...
Coach101   I think the 8086 was designed by a hardware "weenie" and the 68xxx
           (which I think is the best a
AFL Dyfet  And let's not forget while loops controlled by nested trinaries
           :)...
Coach101   architecture available) by a software architect :)
Coach101   Done.... ga
RonLichty  I'd have to agree with most of that
RonLichty  I was really comparing C with Pascal regarding it's
RonLichty  write-only nature.
RonLichty  I think of C as a language you can twist into a moebius strip or
RonLichty  maybe a Klein (sp?) bottle.
RonLichty  C can be as straight-forward as Pascal, but bad
RonLichty  programming practice often twists it otherwise.  :)_
RonLichty  I would also suggest
RonLichty  assembly as the language to use on the IIGS for animation
RonLichty  and in some situations for tight loops.
RonLichty  Code that has to run fast, so is optimized in the midst
RonLichty  of a C or Pascal program by translating that code
RonLichty  into assembly.
RonLichty  Most commercial programs
RonLichty  I know tend to be written in C or Pascal with
RonLichty  lots of drops into assembly when necessary
RonLichty  (though, of course, there are many commercial programs
RonLichty  written in assembly entirely on the II and IIGS).
RonLichty  We wrote the IIGS Sales Demo program in assembly
RonLichty  in part to optimize for speed and in part because that's all there
           was!  ga
AFL Dyfet  One should consider that unix is written in C (for good or bad
           :)...A good C
AFL Dyfet  compiler will allow you to mix assembly code fairly easily when
           you need it,
AFL Dyfet  and can be used to write fairly easy to maintain code...(or can be
           abused :)...
AFL Dyfet  I believe Floyd had a comment...GA Floyd...
AFL Floyd  In reference to terseness, it is very helpful to make sure one's
           variable,
AFL Floyd  constants and function names are as descriptive as possible. 
           Doing this in
AFL Floyd  my code almost makes it self-documenting.. I prefer C for a
           high-level
AFL Floyd  language, but my C code isn't very terse.  It looks more like
           Pascal (which
AFL Floyd  used to be my favorite high-level language.) ga
AFL Dyfet  I prefer C because I find less road-blocks between me and what I
           am trying to
AFL Dyfet  do than in Pascal, where the compiler carefully controls what you
           can and
AFL Dyfet  cannot do...I often prefer to focus on trying to get the job done,
           and not on
AFL Dyfet  how the program should be made to look.
AFL Dyfet  Go ahead Floyd...
AFL Floyd  Even though I prefer C I think Pascal is the best first language
           to learn. ga
AFL Dyfet  I tend to agree, since Pascal does force the person to think and
           methodize what
AFL Dyfet  they are doing...Okay, I believe that SSSi has the next
           question....GA SSSi...
SSSi       Ron: hope we will see some resources attached to the Finder
           someday soon? As
SSSi       far as languages are concerned, I've used them all, but
SSSi       find that I am able to control the "vertical and horizontal"
SSSi       alot better in Assembly. Pascal is great for a beginning, but
SSSi       doesn't allow alot of the flexibility that I get from C. C is
           great too,
SSSi       but I spend alot of time in the debugger (my fault), and I find
SSSi       that what I see is what I get. I really do think that a
           programming
SSSi       language is a presonal kind of thing, something
SSSi       that each programmer has to try and decide for one's self. GA
AFL Dyfet  Go ahead Coach...
Coach101   If one is programming for personal enjoyment, then the language is
           a personal choice....
Coach101   If one is programming for a living, assembly is just NOT a choice
           anymore.  Find the high level
Coach101   language you like best and use that with drops into assembler as
           needed for speed or system
Coach101   interfacing.   ga
AFL Dyfet  Okay, I believe that A2 has the next question...GA A2...
A2GS       Ron, I realize (of course) that you can't vomment on unreleased
           products, but..
AFL Floyd  (Please, no vomiting!) ;)
A2GS       any possibility of getting a Mac FST in a future SYS. Disk? GA  (1
           more Q to
A2GS       follow, after)
A2GS       Ooops  :)
RonLichty  You're absolutely right, A2.  I cannot comment on unreleased
           products!  ga
AFL Dyfet  Okay, Go ahead with 2nd question A2...
AFA Gary J :)
A2GS       Any news on the '832?  (your closer to WD then I am :)
RonLichty  No, I don't have any news on the '832.
RonLichty  Bill hasn't been keeping me apprised of his progress
RonLichty  ga
A2GS       one comment....
A2GS       About languages, you knew it was coming...
A2GS       I think for pleasure use, any High level language that makes the
           programmer
A2GS       happy should be used, but on a professional side who is writing a
           program
A2GS       that the general public will have to use, he/she should use
           Assembly for
A2GS       quality reasons, or for know other reason then to offer the best
           speed]
A2GS       available to the program on the machine.
A2GS       GA
A2GS       know = no
AFL Dyfet  Okay, GA Dave...
Dave Lyons On the other hand, if you choose a very *small* amount of the code
           to put in
Dave Lyons assembly, leaving the rest in some high-level language, you can
           usually get all the speed
Dave Lyons that the user is going to notice.  Also, for applications
Dave Lyons that spend most of their time inside toolbox calls anyway, it
           doesn't make that much different
Dave Lyons what language the app was in.  I don't have *strong*
Dave Lyons preferences for any particular language...have written in
           Assembly, Pascal, and C, with a
Dave Lyons preference for C over Pascal if I've got a good working
           implementation.
Dave Lyons What *does* bug me is when I talk to
Dave Lyons somebody who has written an application
Dave Lyons in assembly & done something in a shabby way because
Dave Lyons they didn't bother inventing a complex enough data structure,
           which would have been easier in
Dave Lyons Pascal or C.  (OTOH, I've seen people use fixed-sized arrays in
           high-level langauges, too,
Dave Lyons for no good reason.)  ga
A2GS       <---Not bothering to argue, his points make sense  :)
AFL Dyfet  Thank you Dave...Okay, I believe the next question is from Doctor
           Why...GA.
Doctor Why This is off the topic, but..... I have a cursor defined as a
           resource and would
Doctor Why like to use it in an ORCA/Pascal program. The ? is how?
AFL Dyfet  Go ahead, Dave...
Dave Lyons Make your resource "fixed", and call LoadResource to get it into
           memory.  Dereference the handle
Dave Lyons and feed it to SetCursor, with any necessary type-casting.  For
           example,
Dave Lyons CursorPtr myCursor;   myCursor = (CursorPtr)
           (*LoadResource(rCursor,1L));  ...
Dave Lyons SetCursor(myCursor);    (course, you should check for an error on
           LoadResource)  You may want to
Dave Lyons mark the resource "preload" in addition to "fixed".  ga
Doctor Why Thanks, I'll give it a try.
SSSi       Yup! Also, make sure the current resource is your application or
           NDA! GA
Dave Lyons (the current resource *app*, eh?)
AFL Dyfet  :)
SSSi       :)
AFL Dyfet  Okay, any further comments or questions for tonight?
AFL Dyfet  Okay, I would like to thank Ron Lichty for stopping by
           tonight...
A2GS       Thanx Ron!
AFA Gary J Yes, thanks for stopping by, Ron.
A2GS       Ron, Any more books in the works??
RonLichty  No.  I'm still trying to recover from the last one.  :)
A2GS       Are the tech note(s) for writing an FST available?
A2GS       yes/no/maybe?
AFL Dyfet  A2, there are no tech notes for writing FST's because Apple has
           reserved the
AFL Dyfet  sole right to itself for tampering with the OS...
AFA Gary J Never, A2
Dave Lyons A2GS, your question is misleading by using the word "the" in
           front
Dave Lyons of "tech notes for writing an FST", because there aren't any...the
           policy has been, and continues
Dave Lyons to be, that Apple doesn't support 3rd-parties writing FSTs.  There
           are some decent reasons
Dave Lyons for this, that I won't repeat here unless somebody really wants
           them, given the current FST design.
A2GS       That what I thought  :(
AFL Dyfet  To put it simply, FST's are DANGEROUS, and subject to failure on
           future OS
AFL Dyfet  releases...
Dave Lyons Yes, definitely.
AFL Dyfet  They are not streight forward, and there is no clearly/cleanly
           defined
AFL Dyfet  interface for them in GS/OS...
A2GS       Well, if their written in the same form (design) as the already
           written FST's..
Dave Lyons Right, they *look* like the same kind of thing Device Drivers are,
           but they aren't.
A2GS       there shouldn't be any hazards, providing they are bugless.
A2GS       which is a BIG provision of course.
Dave Lyons The catch is that Apple reserves the right to make changes in the
           way the OS works that *require*
Dave Lyons changes to *all* FSTs.
Dave Lyons It doesn't have to be a big change, either.
A2GS       I take it that the FST's do low-level work?
AFL Dyfet  Very
Dave Lyons Yes, and fairly high-level work *too*.  For many GS/OS calls,
           GS/OS does little more than pass
Dave Lyons the call along to the appropriate FST.
AFL Dyfet  FST's call the undocumented and volitile internal GS/OS micro
           service call
AFL Dyfet  block as well for certain management operations.
Dave Lyons True. (the "system service" vectors at 1FCxx)
AFL Dyfet  One option I would like to see in Finder is a preference to
           disable exploding
AFL Dyfet  windows...
A2GS       On a serious note, Ron, I would like to see a "Coomand Window"
           option in which
A2GS       you would be able to TYPE commands in for those which are not
           available or
A2GS       incapable of being reproduced on a totally mouse based system.
A2GS       Any possibility??
Dave Lyons What commands are incapable of being reproduced on a totally
           mouse-based system?
A2GS       Filename search for one.
A2GS       And about a million more which are avaible under UNIX (which I
           generally hate)
A2GS       but have never used.
Coach101   How about a "trainable" Finder (like the documentaion said would
           work)?
Dave Lyons (Find File does it without having a command window!)
AFL Dyfet  (And to disable visual window closing when launching an app...just
           shut it
AFL Dyfet  down, clear the screen, and bring it in)...:)
Dave Lyons Dyfet, it already doesn't visibly erase the windows, *except* for
           clipboard and trash.
A2GS       What about "Delete block of files on Device which fall under
           certain conditions
A2GS       "
Dave Lyons What about "select files based on name, mod-date, etc" and then do
           any allowed
Dave Lyons operations on them, including dragging to the trash?
Coach101   The things I want most in Finder are: 
Coach101   1) Be able to put Folders on the desktop
AFL Dyfet  Yes!
Coach101   2) Allow Finder to create Finder.Data files on servers.  I hate
           having the location a function
Coach101   of what was last done a Mac!
Coach101   I am not sure if this is there in IIgs FInder, but
A2GS       Dave, generally, a command window will allow practically limitless
           expansion
Coach101   how about being able to copy a file from folder to folder (as
           opposed to *move*)
A2GS       instead of having to deal with mile-long pop-menus or PDM's.
Dave Lyons I'm not talking about long menus--just one item that would give
           you a dialog letting you specify
Dave Lyons properties of files, and then just *select* the files.  That way
           you could build on the knowledge
Dave Lyons the user already has--once they discovered Select Files..., they
           could use it with all the
Dave Lyons things they already know how to do (like drag-to-trash).
A2GS       A little bit limiting...but basically is the same as my
           request...any comment
A2GS       Ron??
Dave Lyons Coach, I guess we're missing that feature (copy to another
           location on the same volume, without
Dave Lyons using Duplicate & having to rename the copy later).  On the Mac
           finder it's just option-drag.
Dave Lyons Problems w/ my idea: does this mean you can have things selected
           in several windows at once?  Can
A2GS       Don't quite follow coach's prob.  could you explain it again?
Dave Lyons you have things selected that aren't in open windows?
A2GS       Coach?
Coach101   I know....   Ever forget your on a IIgs when you copied a file?
RonLichty  I'm listening.  But not doing any promising, of course.  :)
Coach101   If you drag a file between folders on the same voluem, Finder
           deletes the file from the source
Coach101   folder and places the file in the destination folder.  That is a
           MOVE and not a COPY...
Dave Lyons (Well, it just CHANGE_PATHs it.)
AFL Dyfet  I would suggest that if people have serious comments about
           improvements for the
AFL Dyfet  Finder, that we start a message topic for it...
Coach101   On a Mac if you do the same thing but hold the OPTION key down,
           you get two copies of the file
Coach101   One in the soruce folder and one in the destination folder..  
           OK?
A2GS       Oh...
A2GS       Ok.
Dave Lyons ok
A2GS       A way of duplicating a file, in other words.
Coach101   Dave, I know, but its easier to expalin as copy and delete  :)
A2GS       Thanx for coming Ron and returning back to GS developing  :)
RonLichty  please ABSOLUTELY feel free to email them to me.