Videopac Programming
(sorry for the bad layout, but
this page is for a functional purpose only, not to represent anything ... if
you don't like it, don't use it)
here's some info for programming the Videopac/Odyssey2 - you can find some roms
and sourcecode written by myself, technical info and links to some useful
sites:
Unofficial O2EM Port
Here's a page for my unofficial O2EM Port - my own version of O2EM with some new features (better debugger for developers, supports 2 real PC-Joysticks and more)
This page also contains all info needed to compile o2em for yourself on a windows platform.
Links to other sites (take a look at those first before trying to use anything on this site):
Videopac
Programming page of Soeren Gust - downloading (and reading!) his pdf is a
very good starting point ...
Rene G7400's Site
(lots of hardware info to be found here)
videopac.org
Forum - just take a look around, not only for programming purposes!
some things i wrote:
(Legend for Controls: u = up, d = down, l = left, r = right, b = button, e.g. u / d +b means up or down with button pressed)
g7400src.txt - a documented G7400 ROM-Source - contains just the parts different from the original g7000src.txt found on Rene's site
Spritebuilder - sp_build.rom - Source
a little utility for use on O2EM or a real videopac machine
to test combinations of 2 characters and build new sprites (like the ones used
in e.g. "Killer Bees" ... or the guy with the funny hat in the screenshot)
Controls:
|
Stick |
Movement |
Action |
|
0 |
u /
d / l / r |
Move
character 1 |
|
0 |
u /
d + b |
Scroll
up/down in character map for character 1 |
|
0 |
l /
r +b |
Change
color (+/-) of character 1 |
|
1 |
u /
d / l / r |
Move
character 2 |
|
1 |
u /
d + b |
Scroll
up/down in character map for character 2 |
|
1 |
l /
r +b |
Change
color (+/-) of character 2 |
WARNING:there is no code to check for character overlap, so using this on the emu produces different results on overlapping chars than using it on the real machine - I left it out because I wanted to try to find possible effects of overlapping characters ... nothing useful yet
Soundfinder – sndtest.rom - Source
lets you control the sound registers of the Videopac and find out, what the values mean and which sounds are produced with different settings of the control register. Shows the contents of the three data bytes and the control byte.
Controls:
|
Stick |
Movement |
Action |
|
0 |
u /
d |
Byte
1 + / - |
|
0 |
l /
r |
Byte
2 + / - |
|
0 |
u /
d + b |
Byte
3 + / - |
|
0 |
l /
r + b |
Sound
off / Sound on |
|
1 |
u /
d |
Noise
off / Noise on |
|
1 |
l /
r |
Shift
= 0 / Shift = 1 |
|
1 |
l /
r + b |
Play
Once / Loop Sound |
|
1 |
u /
d + b |
Volume
+ / - |