home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Der Mediaplex Sampler - Die 6 von Plex
/
6_v_plex.zip
/
6_v_plex
/
DISK3
/
DFUE_100
/
MEGATXT.ZIP
/
GENDEV.TXT
< prev
next >
Wrap
Internet Message Format
|
1994-02-07
|
10KB
Received: from netcom.netcom.com by busop.cit.wayne.edu (Mercury 1.0);
Fri, 11 Jun 93 18:00:40 EST
Received: by netcom.netcom.com (5.65/SMI-4.1/Netcom)
id AA15735; Fri, 11 Jun 93 15:06:13 -0700
Date: Fri, 11 Jun 93 15:06:13 -0700
From: dash@netcom.com (David Ashley)
Message-Id: <9306112206.AA15735@netcom.netcom.com>
To: carl@busop.cit.wayne.edu
Subject: Re: Availability of Genesis Cross development system on Amiga
Genesis Development System Frequently Asked Questions
Q:What is the Genesis Development System?
A:The GDS is a cross development system that lets you develop games and other
software to run on the Sega Genesis. The system consists of a 4 inch by 8
inch printed circuit board that plugs in the cartridge slot of the Genesis,
and has a cable going to the parallel port of the host computer. A complete
software set is included consisting of an integrated editor/assembler, a
stand alone assembler, a symbolic debugger, a music and sound effect editor,
a utility to break standard 16 color IFF images into tiles to be downloaded
to the Sega, and other files.
Q:Does it come with any source files?
A:You get source to the music editor, source to a Z80 program to run on the
genesis to interpret the music files, source to a demo program that plays
music and has sprites bouncing around behind the Sega logo, source to the
editor, source to the download utilities. Complete source is provided
on communicating between the host machine and the Genesis.
Q:How much memory does it have on the board?
A:It comes with 1.25 megabytes of memory. 1 meg is intended for program
development and .25 megs is intended for variable storage for the debugger
and scratch memory
Q:Can you program CD games with it?
A:No, unless you were to write an emulator for the CD rom that could send data
over the normal cable from the host machine.
Q:Does it include technical specifications for the Genesis?
A:Yes, it comes with descriptions of the memory map, graphics registers, the
Z80's functions, reading the joysticks, sprites, scrolling, tiles, the
DMA copier, the audio chips-in short everything required to program the
genesis. Also I provide a working demo with source.
Q:Is this proprietary information stolen from Sega?
A:No, the information on the Genesis came from reverse engineering it,
completely independent of Sega. There are no copyright violations in the
purchase or sale of this development system, nor is there anything illegal
about any use of it.
Q:How does it work?
A:The board has ROMs on it that contain the monitor and debugger that runs
on the Genesis. When the Genesis is reset, the ROMs take over and wait for
commands to come from the host machine-commands like download bytes, send
bytes back, set up registers, define a symbol, or enter the interactive
debugger. When in the interactive debugger the host machine acts as a
terminal, and characters are sent over the cable. Full 68000 debugging
is possible, including disassembly, single step, register view and modify,
breakpoints, expression evaluation, memory view, modify, search and copy,
symbol definition, memory compare. There is also a z80 disassembler built
in.
Q:How does the editor work?
A:From within the editor through single keys you can assemble your file,
move the cursor to errors, enter the debugger on the Genesis (editor becomes
terminal), download code and data, download code only (for faster
development). The editor also has a powerful command language for text
manipulation.
Q:What about the assembler?
A:The assembler is a full macro 68000 assembler, and includes the full 8080
and parts of the Z80 instruction set. It generates symbol table information
that can be downloaded to the Genesis to allow for symbolic debugging. It
is quite fast-on a standard Amiga about 40,000 lines/minute, on a 68030 at
33 Mhz it runs at about 220,000 lines/minute.
Q:Can I program in C?
A:If you have a C compiler that can generate a binary, you can download
it to the Genesis, but it wouldn't be as convenient. This system is geared
towards assembly language development, where it really shines.
Q:How do I make artwork? Is there a sprite editor?
A:Originally I planned on including a simple graphic editor, but I found that
no one used it-instead they used Dpaint. The best way is to use dpaint to
create graphics in lo-res 16 color mode, then to use the utility I provide
to converte them to raw data to be sent to the Sega. Animation can be done
within Dpaint. Unfortunately there is no editor for manipulating giant
figures made out of sprites, but in principle it would be possible to do. So
probably you will use dpaint or some other painting program to create the
artwork.
A:Can you backup existing cartridges like the game backup systems?
Q:No-this system is intended for game development. However if you were able
to obtain ROM images, they can be downloaded just like original code, and
they would run on the system, keeping in mind the 1.25 megabyte memory
limit to the board. When running a ROM under the system, you can tinker with
memory, modify gameplay, add lives, etc. You can do all the normal debugging
functions, like single step, breakpoints, etc, to see how the program is
working. Making a cartridge reader requires some hardware expertise, but is
fairly straightforward. I can provide information on how to do it.
Q:How fast are downloads?
A:Data is transfered a little over 30K/second unless the host machine is old
or slow. That rate is valid for an accelerated Amiga or a 486, and probably
a 386 as well.
Q:What host machines is this available on?
A:Currently the complete system is available on the Amiga. With the purchase
of a bi-directional parallel port that is PSII compatible the system can
work with the IBM, but the software has not been ported completely yet. From
the IBM you can enter the interactive debugger, but the editor/assembler
has not been ported.
Q:Why should I buy your system and not go through Sega?
A:If you can get Sega to listen to you and you can afford to pay $5000 for
their system, then there isn't much advantage to buying from me. It's been
my experience that Sega is very hard to deal with, and unless you're a big
company they will ignore you. If you buy this system, you don't need to sign
away your future, you don't need to sign any non-disclosures. You immediately
have the ability to create software for the Genesis. If you create a game,
you can then sell it outright or attempt to publish it yourself-never having
to pay Sega a dime, as they provided you with nothing and you have no
agreement with them. This system gives you options. Moreover it may be a
better system to develop on that the one Sega provides, but I don't know for
sure as I've never seen theirs-I've just heard rumors.
Q:How long has this system been available?
A:It first became available in April 1991.
Q:Have any cartridges that are already out there been developed with this?
A:To the best of my knowledge, no.
Q:Why is that?
A:I don't know. I provide everything you need to make games for the Genesis.
Q:How many have already been sold?
A:I've sold around 10 units so far, although I've done no advertising other
than leave a brochure at the 1991 Game Developer's conference. I haven't
really been serious about marketing it in the last two years.
Q:How much does it cost?
A:The cost is $1000, and the full software is available only on the Amiga.
Q:Will it be ported to other platforms?
A:If there is enough demand it will be ported to the IBM. I have no plans to
port it to the Macintosh. The problem there is the Mac has no 8 bit bi-
directional parallel port other than the SCSI, and I don't know if the board
can connect to a SCSI. What is needed are 8 IO lines, and one line coming
from each machine and going to the other, and ground of course. Also the
Mac is expensive, but the IBM is cheap cheap cheap...
Q:Are there dealer discounts? Or if I want to buy several at once would it be
cheaper?
A:Yes-if you buy three the price is $700 per unit. If you buy more we can
work out a deal.
Q:If I buy the system for the Amiga, how much would it cost to upgrade to the
IBM when and if it becomes available? Would the system work on the IBM then
or would I have to modify it?
A:That would be free if you cover postage. Also EPROM support is free if you
send back your old EPROMS and cover postage. The board would work with an
IBM providing you have a bi-directional parallel port. One is available from
Fry's electronics for $59. The board connects to the host machine through
a DB25 connector-the host machine must be female. There is no internal
connection necessary.
Q:What about technical support? How about software upgrades?
A:You can send me email and I will answer questions and help solve your
problems. If I'm home you can call me. Concerning software support: I want
you to be happy with this. If you want some program written, and it seems
like a good idea, chances are I'll do it for free and include it with the
system. Currently if the software seems sparse it's because no one has
complained so I guess I include enough. There's no point in writing
software if it isn't going to be used. In any case software upgrades are
free unless it's some major upgrade like including a C compiler-I don't
believe in selling something for hundreds of dollars then nickel and diming
you on upgrades.
Q:Do we need to pay you any royalty on games developed with the system?
A:No. Once you bought the system you can do anything you want with it-except
copy it and sell it yourself...
Q:What about those pictures in the National Enquirer?
A:I don't know what you're talking about.
Q:How can I contact you?
A:Send me email or call- my number is 818-584-0357, dash@netcom.com