#13227 - The Traveler - Tue Dec 09, 2003 3:28 am
hey guys, im new to this board, and just had a few basic questions id like to settle before I open my wallet and pick this stuff up. If you dont know the answer thats cool, it just saves me of hours of reading random posts.
(im planning on getting EZFA : EZ-Flash Advance USB)
1. Regarding the bootmenu, does it act as a UI/OS? And how is it installed. If i formatted my flash cart, what happens to the bootmenu?
2. About the general memory sizing. When it says 256M is that megabytes or begabytes. I noticed it says you can only store 8-10 games.. but each games is only like 2megs.. so how does that make sense?
3. mp3 playback, how many mp3's could you really fit on a 256 cart at say medium bitrate, and how good is the qaulity of the GBA sound card.
4. video playback, how much compressed footage would actually fit on a cart? Again, back to question 2 about megabytes/bits
5. if i loaded say, 2 games, an mp3 player and an image viewer. And also 2 mp3s and a jpg, when i go to the bootmenu, would i see all the files, or just the equivelent GBA files, ie: media player, picture viewer, game1, game2
6. to anyone who owns the EZFA realtime 256... pros cons??
thanks alot guys.. Sorry if these questions seem trivial, or if they have already been asked/answered millions of times.. I just couldn't find this stuff anywhere... Thanks again in advanced
#13228 - tepples - Tue Dec 09, 2003 4:34 am
In general, you might have better luck on the gbaemu.com boards.
| The Traveler wrote: |
| 1. Regarding the bootmenu, does it act as a UI/OS? And how is it installed. If i formatted my flash cart, what happens to the bootmenu? |
With most GBA flash carts, the boot menu is merely the first ROM on the cart, and it's erased when you erase the cart.
| Quote: |
| 2. About the general memory sizing. When it says 256M is that megabytes or begabytes. |
Megabits. A 256 Mbit card can hold up to 32 megabytes, but no, you can't use four 8 megabyte commercial ROMs because the menu itself takes about 32 KB. You have to either remove at least 32 KB of zeroes from the end of one of the ROMs or use three 8 MByte commercial ROMs and several homebrew ROMs.
It's not really MP3. The "MP3 playback" programs for GBA actually decode the MP3 to .wav and then re-encode it to some other format that a 16 MHz processor can easily decode.
| Quote: |
| how many mp3's could you really fit on a 256 cart at say medium bitrate |
My 8ad codec operates at 73 kilobits per second; one 256 Mbit cart can hold up to an hour of 8ad audio. It can hold more if you're using .mod, .xm, or .s3m.
| Quote: |
| how good is the qaulity of the GBA sound card |
The 8ad codec nominally runs at 18 kHz sample rate, 8 bits per sample. This is good enough for jogging.
| Quote: |
| 4. video playback, how much compressed footage would actually fit on a cart? |
Full-motion video is in general not worth it. If you're looking to make a game, use sprite animations instead.
| Quote: |
| 5. if i loaded say, 2 games, an mp3 player and an image viewer. And also 2 mp3s and a jpg, when i go to the bootmenu, would i see all the files, or just the equivelent GBA files, ie: media player, picture viewer, game1, game2 |
Depends on your boot menu software. PogoShell can show "all the files" as you'd expect from a file manager, but PogoShell currently doesn't support EZ-Flash well (it does support F2A, which uses familiar Visoly bankswitch handshaking), so you're stuck with the boot menu software that comes with EZ-Flash, which I haven't used.
_________________
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#13230 - The Traveler - Tue Dec 09, 2003 7:36 am
Thanks alot man!
Cheers
#13251 - dagamer34 - Wed Dec 10, 2003 1:17 am
Just to save you more time... The GBA can't decode straight .mp3s in real-time. Its not really designed for that kind of thing.
And using a codec is kind of a hassle. Maybe you could get a MP3 player?? (not to be mean)
Tell me if you like it by the way, I plan on getting one too!!
_________________
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#13269 - The Traveler - Wed Dec 10, 2003 7:15 am
Well, im not getting it for mp3 playback.. i just think id be cool to be able to listen to mp3's on a gameboy... same with watching movies... just another usless, but very cool thing ..
aha.. im picking it up this weekend.. ill let you know
#13279 - mathieu - Wed Dec 10, 2003 5:07 pm
| Quote: |
| Megabits. A 256 Mbit card can hold up to 32 megabytes, but no, you can't use four 8 megabyte commercial ROMs because the menu itself takes about 32 KB. You have to either remove at least 32 KB of zeroes from the end of one of the ROMs or use three 8 MByte commercial ROMs and several homebrew ROMs. |
But, don't GBA programs all assume they start from adress 0x08000000 (from the cart) ? If you use a menu to load a program, and that the menu is itself at the beginning of the cart, how does it work ? The ARM7TDMI doesn't enable the developper to do some virtual memory management, if I can remember well, so all the jumps and absolute memory locations coded in the program (that we want to start with the menu) will be trashed.
Any clue on how that kind of "menu" could work ?
#13280 - ampz - Wed Dec 10, 2003 5:39 pm
Mathieu:
There are several ways to do that. The flash carts have a built in offset fetaure where the menu program can change the flash memory offset. That way any program can be but just about anywhere on the cart. (usually on any even 32kB block or so). This is how most menus does it.
The other way is to put a game right at the start of the cart, but change the branch instruction on address 0x08000000 to branch to the menu program (located elsewhere) instead of the game. The menu program can branch back to the game later. Not sure if someone uses this way, it is a bit more complicated, but it can save some cart space.
#13282 - tepples - Wed Dec 10, 2003 5:58 pm
| ampz wrote: |
| The other way is to put a game right at the start of the cart, but change the branch instruction on address 0x08000000 to branch to the menu program (located elsewhere) instead of the game. |
Some of the pirate GBA multicarts do this. Typically, these will have only one proprietary GBA game, and the rest are either open-source games or PocketNES, both of which can be relinked to start at another ROM base address.
_________________
-- Where is he?
-- Who?
-- You know, the human.
-- I think he moved to Tilwick.
#13353 - dangpride - Thu Dec 11, 2003 6:41 pm
hi,
i'll get my ez-flash card 2morrow. somebody said that the booter is the first rom on the card, and if the card will get formated the booter will be erased to. do i really need the booter then??? what is the booter for??? will the card not work without the booter?
and what's the probelm with ez-flash and pogoshell?
isn't there a booter in pogoshell?
thanks for everything
dangpride
#13355 - tepples - Thu Dec 11, 2003 6:57 pm
The menu software is stored on the PC. If you tell the transfer software to write only one ROM to the cart, it probably won't write a menu; instead, the cart will just boot to the only ROM you wrote. At least this is how the Visoly software worked.
PogoShell has a booter, but it only works with Visoly and F2A cartridges. You see, Visoly and F2A carts do bankswitching one way, but EZ-Flash and XG-Flash carts do it another way, and the author of PogoShell hasn't been able to do much to get PogoShell to talk to EZ-Flash carts without actually owning an EZ-Flash cart.
_________________
-- Where is he?
-- Who?
-- You know, the human.
-- I think he moved to Tilwick.
#13362 - dangpride - Thu Dec 11, 2003 11:18 pm
hi thanks for the answer.
so does that mean that i can't do nothin at all with pgoshell on ezflash ???