[Coco] Hi! I'm new here!

[Hugo Dufort]

Hi! I am new in this group, so let me introduce myself, and explain how 
I got interested in the Coco community and what I expect to find here.

My name is Hugo and I'm 41 years old. I live in the southeastern corner 
of Quebec, Canada.

My parents gave me my first computer, a Coco2 with 64kb memory and a 
tape recorder, when I was in 4th grade (10 years old). I started playing 
games and learning Basic programming quite fast. I would say I was 
motivated and perhaps talented. I learned to read binary and hex 
numbers, and I also learned how to peek/poke in memory. However the 
possibilities were limited (I had no printer and an old black & white 
TV) and I've lost many Basic programs due to IO Errors and cassette 
mismanagement. I spent afternoons playing Wilcatting, Sea Dragon or 
Zaxxon. Still, I had discovered how to bring up the semigraphic modes, 
and programmed a few nice games in these modes. I also discovered a 
pixels pattern that made the pain() function overflow, so I wrote my own 
better paint() function for pmode4.

Things changed when the Coco3 was launched. I kept bugging my parents 
till they bought me one. Then I pushed until they bought a dual diskette 
unit, a DMP-105 printer, and the better (white) Joystick. I also 
received many nice programs such as CocoMax 3 and a banner printing 
application. I started learning how to better program with the Coco3. I 
wrote a few useful applications:
- A program for reading bitmaps from disk, writing them on screen, 
dithering and adjusting colors, and printing.
- A basic word processor, which I used to write many homeworks and 
personal files. It worked just fine, had adjustable margins, and even 
printed accented characters properly.
- An utility that physically read disk sectors and tried various cypher 
values to decode adventure game texts.
- A few nice games, which I exchanged for commercial game diskettes at 
the local computer club (!)

I remember I was able to poke my way around the hi-res graphics modes, 
using a reference page I had photocopied. I also remember mastering the 
paging functions in the MMU. Go figure.

Sadly, when I decided to move to the PC world in 1993, my parents asked 
me to sell the Coco3 and all the accessories.

Later, when I was at the university in 1996, I visited a friend at my 
old college and learned that they were selling old computer stuff. I was 
shocked/delighted to find that they were selling a fully equipped Coco3 
with 512k, IO prototype boards, joysticks, quad diskette drive, EDTASM+ 
cartridge with all docs, OS9 Level 2 disks, etc. for 60$. I wasn't rich 
at the time but managed to find enough money to buy the whole cardboard 
box. Since I was studying in Computer Science, I started messing around 
in EDTASM+ and for the first time in my life, programming some actual 
assembler. OS9 really baffled me -- I never imagined the Coco3 could use 
such a sophisticated system. At the time I was doing lots of programming 
at the university on Unix text terminals, and it was nowhere as easy to 
use as OS9.

I didn't have enough space in my university room for both my PC and my 
Coco3 so I left the latter at my parents' house. At some point, since I 
was almost never home, my mother decided to redecorate my old room, took 
many cardboard boxes full of "wires, old books, parts and junk", and 
simply dumped them on the roadside for someone to take it. So this is 
how I've lost my second Coco3.

I like a good challenge but I don't have much experience in low-level 
coding. For instance, back in the 1990s, I've programmed a 3D 
labyrinth/adventure game in Turbo Pascal on my 386dx computer. It used 
paged memory to access a full 2 mb, dynamic loading of textures, 
precompiled textures with transparency for faster display, my own 
320x200x256 fast library, and a simple scripting language.

I havent programmed in assembler or on "challenging" processors since 
2001 (I programmed a simple Flash memory management driver for an 
embedded 8088 system at work), and I have "officially" stopped 
programming in 2007, but I am still interested in computers. Since I 
have installed VCC and lots of DSK images, I have rediscovered many 
games on the Coco3, and I've even configured my OS9 Level 2 shell. It 
works just fine, though it seems that some of the Coco3 games using some 
graphical functions are running slow in the emulator.

Obviously I don't have access to any Coco-related hardware, but I use 
emulators. I would like to program a demo and a game using either 
assembler, or a combination of Basic and my own assembler subroutines. 
However I am totally lost right now. Reading the documentation, I can't 
even figure out how to initialize the high-res graphics. I would like to 
first test the functionalities in Basic (init graphics using 
pokes/peeks, vertical/horizontal scrolling, memory copy, etc.)

Right now I'm trying to figure out the high-res graphics using memory 
addresses FF90 to FF9F. I also want to understand how to set & move the 
graphic port adress in memory (MMU banks?) I'd go with 256x200x16 and 
try the scrolling pokes. By the way, is anyone using the 320x225 or 
256x225 modes? Are they useful? Thanks.

Hugo



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