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PostPosted: Tue Jan 13, 2015 6:26 am 
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Pokun wrote:
I think the Everdrive uses the reset line to reset the Game Boy so that the bootstrap should load up again. On Super Game Boy you would have to reset manually though.

Can the SGB reset the Game Boy? If so, the menu could possibly upload a small amount of Super NES code that does the job.


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PostPosted: Tue Jan 13, 2015 6:17 pm 
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There is no SGB command for resetting, but you can send 65816 code so maybe there's a way to reset it like that.

BTW there are apparently games that rely on the initial state. You can detect what Game Boy system the game is running on by reading the accumulator after boot. If it's $FF it's either a Game Boy Pocket or Super Game Boy 2. Tetris DX does this to check if it's running on a SGB2, and if it does it will load up a different SGB border.


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PostPosted: Wed Jan 14, 2015 3:23 am 
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I think the question was whether the SGB hardware itself actually provided means to reset the Game Boy, even if that requires poking into it directly.


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PostPosted: Wed Apr 01, 2015 9:46 pm 
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If you need to reset the Game Boy CPU of the Super Game Boy from software, it should be possible.

You could run code uploaded to the SNES RAM via SGB commands: DATA_TRN/DATA_SND (DATA_SND is more efficient for small transfers, since you don't need to setup VRAM to send the message, you just use the joypad port), then JUMP. You'd need a short 65816 routine to clear bit 7 of $6003 (according to http://www.dforce3000.de/pub/d4s_super_gameboy_notes.pdf). This would reset the GB side, and then you would need to JMP to the reset vector SNES-side to allow recovering from the SGB JUMP command.

Actually, I wonder if the reset handler of the Super Game Boy already causes a GB CPU reset on startup? Then your routine could just JMP ($FFFC) and skip the $6003 writes altogether.


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PostPosted: Tue Apr 21, 2015 2:31 pm 
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I just want to point out that LSDJ support is poor, and the reason I got rid of the device is that it takes ages to load a new rom as it's written to flash memory, rather than loaded into SRAM or SDRAM with an appropriate controller.


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PostPosted: Tue Apr 21, 2015 5:58 pm 
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mikejmoffitt wrote:
I just want to point out that LSDJ support is poor, and the reason I got rid of the device is that it takes ages to load a new rom as it's written to flash memory, rather than loaded into SRAM or SDRAM with an appropriate controller.


It was not meant for LSDJ, it was meant for games. There are other cards more suitable for chiptune musicians. There is something of a tradeoff between the flashing speed of the EDGB and the vast amount of ROMs available on an SD card, but a 4MB ROM can be flashed in under a minute. Its also has vastly improved compatibility for games. Compared to the klunky interfaces and limited ROM support of the LSDJ cards, it is a revelation. Krikzz is also planning to release RAM-based versions of some of his flash Everdrives (SNES, Master Sytstem, Game Gear, Turbo Grafx-16 and Game Boy) which should make complaints about loading times disappear.

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PostPosted: Tue Apr 21, 2015 6:32 pm 
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The RAM versions are always significantly more expensive though, so many people still prefer the Flash versions. My reasons for wanting RAM-based carts are not related to speed at all, I simply don't like the feeling that I'm causing my carts to deteriorate a little every time I load a new game, even though these Flash chips will probably outlive me at the rate I get to use my Flash carts...


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PostPosted: Wed Apr 22, 2015 7:00 am 
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tokumaru wrote:
The RAM versions are always significantly more expensive though, so many people still prefer the Flash versions. My reasons for wanting RAM-based carts are not related to speed at all, I simply don't like the feeling that I'm causing my carts to deteriorate a little every time I load a new game, even though these Flash chips will probably outlive me at the rate I get to use my Flash carts...


Here are Krikzz's comments from February, 2015 from his site, about RAM-based Everdrives :

KRIKzz wrote:
I have plans to release turbo-v2. It will be ram based cart with instant loading and populous support. May be i will implement some ram backup and arcade cards features, but i not sure. Features like wav playback or save states definatelly will not be implemented


KRIKzz wrote:
I already have working sample (: I guess it will be released in next 2-3 months. By thw way, for turbo-v2 i first time used non altera fpga. This cart like a test polygon for new ideas in architecture development, this is different compared to all other everdrive. I have plans to use this experience in next generation of ed-gb, and i hope in ed-gba also. Very small and energy effective devices (:


KRIKzz wrote:
KRIKzz. Is it gonna be the same price point of the current TED?
Yes

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PostPosted: Tue Apr 28, 2015 7:14 am 
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tokumaru wrote:
The RAM versions are always significantly more expensive though, so many people still prefer the Flash versions. My reasons for wanting RAM-based carts are not related to speed at all, I simply don't like the feeling that I'm causing my carts to deteriorate a little every time I load a new game, even though these Flash chips will probably outlive me at the rate I get to use my Flash carts...

This is the reason I pointed out the speed. At the very least some form of naive wear leveling would have been a nice upgrade.

The reason the speed is irritating is that I found myself more frequently choosing games I know and being less willing to explore new ones - if it's going to take so damn long I had better know I will enjoy the game. At that speed, you can compete with the device using an old EPROM dev cart and a 29F* Flash ROM with a PC-based burner. Obviously no competition for portability, but it's just remarkable how long it takes.


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PostPosted: Tue Apr 28, 2015 7:53 am 
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mikejmoffitt wrote:
The reason the speed is irritating is that I found myself more frequently choosing games I know and being less willing to explore new ones - if it's going to take so damn long I had better know I will enjoy the game.

I just pick my games using emulators before copying them to my Flash carts, so...


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