Basics Archives Community Services Programming
Hardware Help About Search Your Account
   Home :: Community :: Newsletter :: Newsletter - November 2000
Newsletter - November 2000

The ticalc.org Newsletter
November 2000 - Volume 3, Issue 11


Letter from the Editor
Calculator News
Ask ticalc.org
Interview with Patrick Davidson


Hi, and thanks for reading the ticalc.org Newsletter!

Another busy month...well, for me at least. Activity in the TI scene has noticeably declined now that many programmers are in school. That's my hypothesis, anyway.

We have decided to suspend Program of the Month award since we don't feel that there's any fair way to administer it so that everyone is satisfied. It didn't seem worth it, so we've stopped it for a while.

For this month's newsletter I've enlisted the help of Nick Bendler, a member of the ticalc.org screenshot staff. He's interviewed Patrick Davidson, the illustrious author of many programs such as Phoenix. Be sure to read what Patrick has to say.

Eric Sun


Another pretty quiet month here in the TI scene, so not much to report on.

Some of the more notable releases this month included Universal OS v1.14 and a bunch of development tools for the 68K calculators, including TIGCC v0.8 and the TIGCC Tools Suite.

There were a couple hardware releases this month as well. A new GtkTiLink was released, in addition to PIXpand, a new expander by Sami Khawan which uses Playstation Memory cards as media.

Hope to see activity pick up again soon.

Eric Sun


At ticalc.org, we often receive many of the same questions. In this column, we hope to address some of these questions for a broader audience. If you'd like to submit a question, please email it to ask@ticalc.org.

Q: Why is this newsletter late?

A: Well, you see, there were these aliens, and... ^H^H^H^H^H^H^H^H^H^H^H^H^H^H. Anyway. It's mostly my fault, due to an exorbitant amount of work in that process commonly referred to as "college applications." Everything is now under control, and future newsletters will be better, and on time. I promise. If you'd like to help by writing articles, please don't hesitate to email me.

Eric Sun


Email: pad@calc.org

Interview Log
Nick How old are you and what level of education do you have?
Patrick 18 and currently a second-year student at UC Berkeley.
Nick What calculators do you have?
Patrick An 82, 85, 86, 89, and a nonworking 92.
Nick What do you plan on majoring in?
Patrick Computer science.
Nick How did you initially end up in this wacky place known as the "TI Community?"
Patrick Well, I was in a junior high math competition called MathCounts where people who reach nationals get free TI-85s. At first, I didn't know assembly programming was possible. Then someone else at my school found the ticalc.org website and told me about ZShell (this was in fall 1996). But, just about all the details were wrong; like I was told it was 10K in size and that its interface resembed the Unix shell. And last, that the ticalc.org web site address was www.ti85.com, so I didn't get anywhere for awhile. I finally realized it was ticalc.org in February 1997, so I went there and downloaded the Z80 docs and parallel graph-link instructions. Anyway, I tried to get my dad to build that cable, and he did build it correctly, but it was not compatible with my computer. At first, I thought it didn't work, but eventually tried it elsewhere, and found that it worked on every computer but mine. Then, I got my dad to make the serial cable also (how nice), and it did work on my computer (this was early April 1997)...so that's when I first became a real TI-community member. Another thing: about a couple weeks before I got the serial cable, someone else at my school had a TI Graph-Link, and installed ZShell and a few games. They were not well-distributed, though, until I 'enlightened' people on how to copy it.
Nick Do you plan on getting any new calculators soon?
Patrick Well, not really, though there are several people who should really be mailing their excess calculators to me.
Nick What was the first calculator assembly program you ever wrote?
Patrick That would be Lunoid: the breakout game which is the "precursor" to Orzunoid.
Nick What calculator do you use most now, and what do you mostly use it for?
Patrick I'd have to say I don't use any calculator significantly more than the others, and I use them primarily for testing games. I sometimes use them for math, but just less often...my math classes now involve either proving theorems or doing symbolic manipulation beyond the TI-89 CAS's abilities, not to mention that that calculators are banned on exams in just about all math classes at Berkeley.
Nick Were you surprised by the success of Phoenix?
Patrick No, not really, it is such a brilliant program I knew it would happen!!!!! Seriously, though, the history of Phoenix is really something that was quite different from what I expected. In the beginning, I certainly never expected that it would be ported to the TI-89. And after it was, I'm rather shocked that the 89 version seems to be more popular than the TI-92 one (although, of course, that's because there are more TI-89 users). Of course, now my TI-92 is broken and I use only an 89, so I have a greater appreciation of TI-89 issues (such as the smaller screen). Also, the reason I didn't expect an 89 version is probably because the 89 didn't exist when I made the first version of Phoenix.
Nick What are some of your plans for the future?
Patrick Even though I might make a few minor gameplay changes to the "classic" 68K Phoenix, all that's really left is to get it to run the same speed on a HW1 or HW2 calculator (this version will be released soon). For Phoenix-Z80, all that's left is to 'finish' it with more level, and features like shield level display, externel levels, etc. (This should be done by the end of the year.) Also, there's the grayscale version of Phoenix on the TI-89/92+, which is the most important right now, as it will hopefully show that TI-GCC is not slow, for it is just as high-performace as 'classic' Phoenix even though it's in grayscale. Other projects, only barely started or not started, which even have maybe a 50% chance of ever being finished: A grayscale Phoenix on the Z80 calculators, a new racing game ('Z-Kart 4D') for the Z80 calculators, some sort of platformer, also for the Z80 calculators (all of which will be in assembly). In TI-GCC, for the 89/92+: some sort of platfomer, and a 3D shooter, like Wolfenstien or Doom. As far as plans not involving calculators, I have no idea. I should graduate from college in May 2002. From then on, I will probably try to go to graduate school, and then....who knows.
Nick Are the rumors of a self-modifying Phoenix true?
Patrick OK...well, maybe not strictly true. Of course, the Z80 version does contain self-modifying code, as any decent game would. Even though the rumor was made up from thin air, I actually have considered some sort of automatic semi-random generation of new levels. But, I wouldn't make it add to its own version number in that case.
Nick How'd you get started in assembly programming?
Patrick My first experience in assembly programming was on the Amiga computer, which had a 68K processor like the TI-89, but programming for it was less boring because it had custom graphics chips you could use in creative ways, instead of just doing everything with the CPU (the very dull choice of the TI-89). I actually became more interested in assembly after seeing the "Euro Demos" on the Amiga. (I tried to code similiar programs, but I was never as good as the orgininal coders.) I first did this in either 1995 or 1996, since I had, for no reason, set my clock to a date that was a year off sometime around then (but I think it was 1996). Anyway, then when I saw the TI-85, I mostly switched to assembly programming on that, and then gradually accumlated other calculators.
Nick Do you have any advice for new assembly programmers?
Patrick Well, the first piece of advice is that for the TI-89 and TI-92+, it's probably better to just use TI-GCC instead. For the Z80, though, there is no easy escape. I would first warn people not to take tutorials too seriously; many of them make little sense, suggest very poor techniques, or even have wrong information. It's probably best to learn to program assembly on a computer first, as then you'll understand the basic concepts throughly (and there are good manuals for assembly programming). Then you need to look at the instruction tables to learn to program on the Z80. Also, while it's a good idea to have a general idea of what you're doing, wasting all of your time making a detailed 'psuedocode' description of your program will probably just frustrate you, an confuse you into writing ineffeicent code if you actually try to follow it. Beyond that, if you are confused about pointers, the only way to figure it out is to practice until you can get it right. It is worthless to discuss pointers in any 'natural' language (e.g. English, French, etc.) as that leads to confuson, so use them only in code, which is un-ambiguous. Also, learn to manipulate binary and hex. And one more thing that is more important than all of the above: never, ever try to think about assembly programming by analogy with TI-BASIC programming. That is the worst thing you can possibly try to do.
Nick Thank you very much, and good luck.


There are two versions of the ticalc.org Newsletter, a plain text version and an HTML version. To subscribe, send an email to majordomo@lists.ticalc.org with either "subscribe newsletter" (for plain text) or "subscribe newsletter-html" (for HTML) in the body of the message. To unsubscribe, simply do the same thing except replace "subscribe" with "unsubscribe".

You can find all issues of the ticalc.org Newsletter in our Community section under Newsletter. The exact URL is http://www.ticalc.org/community/newsletter/.

Any opinions expressed in this newsletter are the opinions of the newsletter editor and/or published authors. By no means are the opinions heretofore expressed to be considered representative of ticalc.org as a whole. Texas Instruments in no way endorses or is affiliated with ticalc.org. Any trademarks are hereby acknowledged as the property of their respective owners.

  Copyright © 1996-2010, the ticalc.org project. All rights reserved. | Contact Us | Disclaimer