Official Rhea Discussion

I don't know why phoebe would operate any different than the rhea. But who knows maybe bug! will work on the phoebe.

 

He did mention that CD+G compatibility was lost versus the 20 min Rhea when he unveiled Phoebe (not a big loss but an example that speaks to the possibility it doesn't perform as well as Rhea) but who knows, maybe he restored that.

 

There is no way for any cart to detect the memory size, unless it has a soft list of titles that need 1mb carts, but then it will also need its own loader code to read the game header for identification. Too much hassle when only 3 neogeo ports need it. AR carts simply are just 4mb since that works the best with the most games. Early ARs in fact only had 1mb on them, since the 4mb cart was not yet introduced...

There are some third party carts which are switchable between 1mb and 4mb, but they use a hardware switch.

One of the differences between 20pin and 21pin protocol was how subcodes are handled, the 21pin ribbon has extra pins used for that. This is why CD+G does not work. But, no games should use subcodes like that, so it should not cause problems with compatibility.

Bug! does something else entirely (loads data as audio or something among those lines), and as I recall it still does not work with Phoebe.

 

Awesome, makes perfect sense-- thanks for explaining that. I'm pretty juiced to be on the preorder list!

 

EDIT: nvmd

 

Is this potentially fixable with a fw update or a limitation of the rhea?

 

I'd like to think so. But perhaps the fpga isn't powerful enough to do the conversion?


I got some boards in yesterday, the pictures look like trash, sorry.





This is exactly how my hardware menu will work:

The sd card connector on the left (which is too think, dumb me forgot the contacts were depressed on an sd card. So I have to get a new a board made or sand the backside down to thin it up) will plug into the rhea. The two pin connector on the topside will go to the sd card detect and write protect lines on the rhea board. You can see that the sd card is notched. So when this card is inserted into the rhea, the rhea doesn't think anything is inserted.

The main board on the right takes an 3.3v arduino pro micro. The board has 4 connectors, Power, LCD, Rotary Dial and SD Card. On the front side there is a spot for an sd card; that is what arduino and rhea will share. They both can't access the card at the same time so that's what the two surface mount chips are for. They are high bandwidth bus chips. (Hopefully they work, in theory they should be haven't actually tested this part yet ).

The software is expecting the folder structure of the sd card to looks like this

Root
/00/ (Dir)
/Games/ (Dir)
Categories (File)
0-9 (File)
A (File)
etc

The Categories file is just a plain text file (no .txt extension but I more than likely add that in at some point) and loaded on startup, in contains just a list of sub files. I my case I did A,B,C. You could do whatever you like though, for example. Fighters, Japanese, Arcade, RPG, Racing etc.. Each of of these sub files contain a list of games. All games must be cdi. The actual cdi file should be in kept in /Games and this filename must match exactly what is in the sub file (minus the .cdi).

When you turn the saturn on, the rhea thinks there is no SD card inserted and the ardunio is always set to have access to the sd card first.

This is the run procedure:
Check folder 00 for game, if found:
------->Check for Config file to get last scroll locations
------->switch bus, at this point the rhea will instantly pickup the card and boot. The only reason a game would be found in 00 is if you just turn off the saturn while playing a game.


If not not found:
------->Get entries in Categories file

Once you select an entry, it reads the next sub file, just like the Categories file. Once you select it a game:
------>Overwrite Config file with new scroll locations
------>Move file from /Games/ to 00
------>Switch bus

While a game is running it displays:

Running:
Bomberman

If you press the button on the running display screen:
------>Switch bus back to arduino (rhea drops sd card)
------>Move file from /00/ to /Games/
------>Return back to previous scroll position

Filenames longer than 16 characters will scroll on the on the screen.
Filenames cannot be longer than 75 characters.
Each time you scroll the sd card is file is read and just two filenames are stored. This is for memory purposes. I'm only dealing with 2.5k sram on a pro micro. If you 40 items in a sub file the memory would be gone if I put this into an array etc. The scrolling is instant at only half spi speed, so its not a concern even with very very large sub files.

I wont be able to do anything more on this until the weekend. I also needed to get some different hookup wire. The connectors are I choose are on the small side (I was trying to keep the boards as small as possible) and are pain in the ass to crimp with the wire I currently have.

 

Awesome work, Citrus! Do you plan on selling these once you have it completed?

 

Hadn't really thought about it. If all goes well I was planning on making everything open source. Gerber files/source code etc.

The surface mount stuff is pretty small, so it will take someone with soldering experience. Also to crimp the connectors requires an specialized crimp tool which costs around 70 bucks. I could however redesign the boards and just have solder pads, if people want it. I just think the connectors will make everything look very clean.
If someone wanted to pay me for materials and time it takes to assemble everything, I'll take their money.

 

Has anybody had trouble using the INI file on the root of their SD to change the region? I'm using .cdi files and I just can't get the images to work without an Action Replay. I've named the file Phoebe.ini, and "auto_region = 2" is the first and only line in the file. I'm lost.

 

So is there an inbuilt menu for it yet?

Recently got mine and its for my games nights, really don't want grubby fingers reaching towards the PCB,
Needs to be simple as I do get the odd numpty (YES ATARI CARTS GO IN BACKWARDS!! TURN THE SYSTEM OFF BEFORE REMOVING THE GAME!!)
Or has anyone modded the upper shell of the Saturn to have a longer button that presses it? (Or have it as the "Eject" button somehow)

I might mod the shell of my Saturn to add a SD card port extender and use a few smaller SD cards instead.

 

If you use an extender just make sure you always turn off the saturn before switching cards.

 

Noted.
I thought that the SD card could be removed while the SS was on
I will end up buying a few small numbered SD cards (1-4gb) and have a few games on each all of the same type and some custom cover art showing what games are on each (SD card wallet?)

Next question is, can I make the button on the shell light up so people can see where to press (this is a problem with my PC engine Everdrive, the bit of plastic I have over it is iffy)

 

An sd card can be removed while the machine is on. But when you use an extender the rhea doesn't know you pulled the sd card. The card detect signal is a physical switch. With an extender the card is always detected because there is always a physical card in the slot. I do not know what would happen if you pull the sd card out of of the extender with something plugged into the rhea. It might still work idk. Just better be safe than sorry.

 

A little post just to say that i follow your work carefully citrus3000psi

 

Just want to let others know who are having the same problem with their Phoebe, I emailed Deunan and he says it's a firmware issue he's currently working on!

 

Ooh. This is good to know. Hopefully the firmware is out soon. I'm supposed to get a Paypal request next week to buy my unit

 

Hi, I was wondering if anyone could help me identify a Victor Saturn for use with Rhea. Victor Saturns seem to be a bit trickier to tell what version it is. Anyone know if this Saturn is 20 pin?

 

Open it up, easiest way to tell is from the inside

 

According to this document https://www.google.de/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CCMQFjAAahUKEwiMu_OM48vIAhXhpnIKHaTZC8A&url=http://assemblergames.com/l/attachments/ss_research_02-pdf.3001/&usg=AFQjCNF9vSQVmZWOJE8dHTYXxE_gpHomnA It's a 21 pin unit, but I'd open it up to be sure. I'm not so sure anymore, might be 20 pin after all.