So, I finally got around to giving the RDP a more thorough test.
The following are some of my findings.
Keep in mind: This portable console was advertised to be compatible with 3 different console's games.


before I get too far, I should note that there was a short circuit with the screen's control board, due to it contacting the tin plate on the back of the LCD. this was causing the screen to go dim at random, or when light pressure was applied near the right side of the screen (or the Y button)
This was fixed by placing some foam pads underneath the LCD to separate the areas that were making contact.
(Why bother the eBay seller when you can just fix the d***ed thing, am I right?)
The innards of the unit are rather simple, very few wires actually soldered on, and could be easily removed.
Considering this, I think that user-level maintenance was indeed in the equation when they made this thing.


The main show (SNES):
This unit was designed to be a portable SNES, and it plays most things with no problem.
All tests were done using an SD2SNES flashcart.
So far, the only game that I found with any problems was Contra 3, which displayed palette issues when in overhead view areas.
Everything seems to opperate about as you would expect, controls work well, and seem to be highly responsive.

Retroport adapter (NES):
This thing is ridiculously huge.
Somewhat wobbly in the cartridge slot, and the securing screw is in a really bad spot where it would be rammed into the pin connector.
That gripe out of the way, it works quite well.
Again, tested with Everdrive N8, most things seem to run with no problems.
Only game with any problems so far was in Zelda 2, where the title screen would try to take the mountain upward with it when the scrolling text starts.
For whatever reason, the electronic backward compatibility in the SNES controller was circumvented, resulting in B and A on the NES being assigned to B and A on the SNES controller, instead of Y and B.

Retrogen Adapter (Sega Genesis):
As found in previous tests, the compatibility is really high with Sega Genesis games, and the Everdrive MD flashcart.
The Genesis 6-button to SNES layout was really well thought out. the mode switch doesn't function, but everything seems to function just fine.
Sonic 2 and knuckles would not boot at all, however no other games appear to have any issues.
Video pass-through was a nice touch.

Gavy (unexpected findings)
In experimenting, I found that not only was this thing compatible with the 3 consoles it was advertised for, but with 3 others as well.

Gameboy (Super Gameboy)
This, should go without question really. the console operates the cartridge hardware, and runs it's system accordingly.
Limited by traits of the SGB

Famicom Disk system (Everdrive N8)
Full FDS rom compatibility was identified with use of the Everdrive N8.

Sega Master System (Adapter/Everdrive MD)
THIS, I didn't see coming. For some odd reason, SMS adapters work with the RetroGen.
Yes, the actual Genesis WAS compatible with SMS, but once detected by the Genesis, it ran on a different chip.
Albeit games are a bit glitchy, I have yet to find any that do not run.

Game gear (Everdrive MD)
Game gear TRIES to run, however the controls do not work and the colors are messed up.
hardware tries to boot in SMS mode, as does the official genesis.
With some conversion hacks existing, some GameGear games CAN be played on both this, and the official hardware.

With that, for the 3 advertised as as compatible, we are brought up to an entire 6. (Not counting game gear)
and with decent compatibility rates to boot.
As far as SNES goes, I would place it on a razor's edge as to if this is better than the Supaboy or not.
But when it comes to the rest of the things it can do, the minor kinks aside, this is definitely one for the collection.

That's really cool! Rarely do products do more than you expect.

Indeed.
I was honestly impressed by this factor.

As a possible mod concepts:

Video/Audio input cartridge:
The retroport and retrogen have an S-Video pass-through in the cartridge pinouts which allow them to operate on the RDP screen.

I noticed that there are two pins marked on both adapters.
One on the expansion pins, and one on the inside pins.

Considering in previous tests, where the audio would pass through on the Supaboy, I feel that it is likely that the inside pin is likely the audio, where the one marked on the outside is video.

S-video would allow for the obvious S-video port, and for AV input. (As the two formats are similar enough to be cross compatible)

This would allow it to be used as a standard TV screen.

Retroport Video out:
Effectively the same concept as before, I would simply ride the S-Video and Audio output and jump it to an external port, allowing it to be used like the retrogen on an actual SNES. (pointless mod really though)

Retroport sawtooth audio channel:
This would be simple enough to do, simply involving jumping the expansion audio pin from the NES input, to a resistor or potentiometer, and then cross to the audio output on the SNES side.


Fun fact: NONE of these actually modify the RDP hardware.

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Edited by: The_Shadow, Jul 21st, 2015 @ 7:34 pm

It would appear that the SD2SNES sucks up a bunch of juice.
This aspect was spotted when I had the battery on the RDP die on me while playing with the charger connected.
(It should be noted, that I was playing for an extended amount of time)

After allowing a full charge, I tested it again by playing a game from the SD2SNES with the charger connected.
after about 5 minutes of play, I shut the system off, and noticed that the charge indicator was signifying that it was recharging.

Similar tests using the Everdrive GB, N8, and MD did not display this problem.

In light of this, I came up with a mod concept, though I have no idea how I might make it work.

SD2SNES Mod Concept: Remote Power source/Battery power.
Find some way to allow the SD2SNES to operate from battery power while connected to a portable device.
Should work in theory, though frying this $200.00 circuit board is a very real possibility. (May not be worth the risk)

Screen dim short circuit fix:
What is actually causing that to happen, is that the screen's control board is shorting out against the aluminum plate on the back of the LCD, we simply just need to place an insulator between them.
So, before we get too far, do note that you will be doing a full dismantle on the unit.
Rest assured though, this is a relatively simple unit.

The first set of screws are located on the back of the unit.

The one holding the battery door on doesn't matter, we won't be going that far into this thing.
Once these are removed, you can pull the back off.


You will notice 2 cables going to the back of one of the boards, they are just held on with a clip. if you are gentle with them, they can be removed.

There are some more screws on the white board that you will need to remove.
once those are removed, we can access the problem area.


You will want to find something to slide in between the metal backplate of the LCD, and the board that it is contacting. I chose foam, but you can likely get away with something such as paper, as long as it prevents contact between these points.


Now, we begin reassembly.


I decided at this point that there might be another possible short at this point, so I applied an additional piece of foam to this area, just to prevent problems in the future.

I doubt I'll ever need to do this, but nice job on the instructions. The photos help a lot.

Yeah, though it's kind of a wake-up-call when someone goes out of their way and registers on a forum with the soul intention of contacting you so that they can fix a problem that you know how to fix.

I had to share this bit of info, if only for the sake that, assuming it is a highly common problem, this allows people to use a really nice piece of equipment.

looks like the sort of fix i could do, now that i have your instructions on how to do it. thanks!

Oh yeah.
This is a pretty dang simple fix.
And no problem. I'm always glad to help.

Sorry for bumping a thread from nearly a year ago, but I thought I should fill you in on things:
The retroport adapter sawtooth sound channel mod has just seen the light of day.
So far just using a long chain of resistors, and a custom pressure contact to the audio channels, this seems to work just fine.

In testing, I also confirmed that the AV-input mod is indeed possible.