modding an Amiga CD32 to RGB

[missyrelm]

Hi,

My wife and I are trying to find someone to mod an Amiga CD32 to output RGB and are looking for suggestions as to who can/will do it.

We am getting ready to buy an Amiga CD32, but our TV is NTSC, and only accepts 60hz signals. So, we are hoping to get around that by modding the CD32 to output RGB instead.

Our Samsung TV’s specs say RGB input, and on the back it says “PC input”, which I am assuming is the RGB.

My understanding is that as far as mods go, this is a pretty easy one, I just don’t know how to solder or read schematics, and don’t want to practice on a classic console.

We have a good history of buying modded consoles and mods of consoles that I provide…
I can provide a list of people I’ve done business with, and also we have an excellent rating on ebay as buyers.

My understanding is that the mod is “just” taking an amiga rgb cable, cutting the db 23, then locate the RGB and video at the TP9 test port near the fmv connector,
where there are pins where you can solder the cable.

Thanks to anyone who can help!

Here is the schematics from the Amiga CD32 FAQ, they aren't showing up right when I copy and paste, so here's the link too:

http://www.faqs.org/faqs/amiga/CD32-FAQ/part2/

CD32 RGB signals...

The RGB signals are available from a test port, TP9...

| | | <--- Kickstart ROM .-. Desc Equiv pin #s
| | | |o|
| | | |o|
| `--' .----. <--- Akiko |o|
| | | |o| HSync 159
| | | : <--- TP9 |o| VSync 160
| `----' : |o| Red 163 and 164
| .. :O.--. |o| Green 165 and 166
`-------'`----------' | |o| Blue 167 and 168
^ ^ `------- |o| CSync 157
| | |o| Ground 161 and 162
Expansion port Pin 182 `-'

The RGB signals come from the D/A conversion unit and lead directly
to the expansion port. These signals are, however, not amplified. In
addition they are weakened by the S-Video output unit.

As a result I (aim to) insert a 47 Ohm resistor to each colour signal
connection. You may also reduce the load by interrupting the signal
supply to the S-Video unit. Set pin 174 of the expansion port to GND
to achieve that (174 --> u36 (4066) signal switches).

The sync signals connected to the expansion port are unbuffered. As
a result you may re-synchronize your Amiga by an external tact
source. You schould at least buffer the CSync line; there is no
external synchronisation possible on this pin.

Hint: make use of an XOR gate chip. You may negate certain sync
line(s) to adapt your Amiga to (old? :-( ) multiscan-monitors (the
A4000 monitor adapter box will do the same; without the possibility
of selected negation).

Written by Klaus Hegemann, posted as part of 'CD32 expansion port
info' by Anders Stenkvist in comp.sys.amiga.hardware, forwarded by
Michael King.

[Soviet Conscript]

you may already know but there is a NTSC version of the Amiga CD32. its a bit rarer but not impossibly hard to find.

[FABombjoy]

PC input may or may not equal RGB compatibility with this console. Have you checked that your TV supports 15khz refresh rates? I don't think that many do, not the ones that label that port "PC Input" anyway.

There also seems to be a neverending supply of NTSC CD32s from China, available new in box on eBay.

[jahvybe]

I have a ntsc cd32. They are pretty easy to come by. Basically commodore went out of business just before they were released in the U.S. so there was a wharehouse full of them that never got shipped. That's why there is the never ending supply on ebay from china.

[missyrelm]

Thanks everyone for all the suggestions...

FABombjoy, I'll have to research the issue of whether or not my TV can take the RGB signal from an Amiga CD32... I don't know a lot about the issue of 15khz refresh rates, and I'd *really* like to be sure this is gonna work before I buy one from China then ship it to someone who will mod it!

What type of TV and connection are you using for your NTSC CD32, Jahvybe? I keep hearing conflicting information about NTSC CD32's and PAL games.... I'd love to hear from a NTSC CD32 owner about this.

Here is where I got some of my information:

What I'd like to confirm is that I have read while researching this that
even when using a NTSC CD32, when it plays PAL games it will switch to the PAL signal after the starting screen, and that it will output 50hz with both composite and S-video, but that RGB would work on any TV that allows for RGB input.

I got this from many sources, including the following


Unless I am misinterpreting it, the Amiga FAQ at
http://www.faqs.org/faqs/amiga/CD32-FAQ/part1/
says that the only way to avoid the 50/60hz problem even when using the “mouse NTSC/PAL changing trick” is to either use a TV that takes both 50 and 50hz or to mod a CD32 to output RGB…

Am I misunderstanding this?

Here’s the quote:

“TVs/monitors connected to the CD32 through the French CD32's or SX-1's
or CD32x's or TP9's (see diagram at end of FAQ) RGB connector will also
work fine.

TVs/monitors connected to the CD32 through the composite or S-Video
outputs won't work though. The problem is that the PAL colour signal is
still sent at the NTSC frequency.”

My understanding is that using a NTSC CD32 will not fix this when playing PAL games,
Here is a quote on the subject:

Here is a quote from Akira on the English Amiga Board..
http://eab.abime.net/showthread.php?t=17615&highlight=cd32+ntsc+pal
“It goes well beyond that, some games will just not run when facing NTSC timing. It's not a matter of having your TV displaying PAL as well...

Besides, NTSC CD32s display 50Hz NTSC instead of real 50Hz PAL when playing in a "PAL mode". The color system is STIL NTSC. So you need a TV that supports 50Hz NTSC (not all of them do, I even had problems with professional projectors in demoparties)

I know, I have an NTSC A1200 and it's quite a bit incompatile with loads of shit. "

So, am I s**t out of luck, or is there a workaround?

[FABombjoy]

I'd *really* like to be sure this is gonna work before I buy one from China then ship it to someone who will mod it!
The eBay/China ones all seem to be NTSC, so you could stick with composite / s-video on those.

[missyrelm]

The eBay/China ones all seem to be NTSC, so you could stick with composite / s-video on those.

I thought the NTSC ones still outputted PAL signals when playing PAL games...
And it seems like most of the games are PAL :(

As I've been doing more research, its starting to look like the RGB is not going to work, which sucks because I was really excited about this console :(

[Soviet Conscript]

i thought only a handful of the games don't work with a NTSC system and even then those ones still play just not perfectly.

[phreak97]

pal and ntsc are seperate to 50 and 60 Hz, theres two main parts to labling a video signal, first is the colour format, and second is the refresh rate. you can run any colour format at any refresh rate. pal format countries all have a standard refresh rate of 50 Hz and ntsc format countries all have a standard refresh rate of 60Hz, so many people think pal and 50hz are the same thing, but they arent. the proper labling for a signal should be pal50 and ntsc60 as the defaults. pal60 and ntsc50 both exist just as easily, though as kinda off-standard, some tv's will be incompatible. if you get an ntsc cd32 itll likely output only ntsc50 or ntsc60 depending on the region it is set to, even if it says pal/ntsc in the menu, it's just confused.. it means 50/60.

now on to being useful.

an ntsc cd32 should always output ntsc, but (if the games do control refresh rate) will switch to 50Hz instead of the american standard 60Hz if trying to display something which is meant to be pal. all this means is that your tv just needs to be capable of 50Hz (not pal), which i think most american tv's are not. even if you use rgb (15khz video will work on ALL tvs btw, its the tv standard.. it's anything else that you have to worry about) you will still have this problem, as rgb is (to make things easy) just another colour format. (think rgb50/rgb60) it wont help if your tv only supports 60Hz.