Author Topic: Is the EDGB limited to 32k SRAM by Hardware?  (Read 3345 times)

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Offline Localhorst86

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Is the EDGB limited to 32k SRAM by Hardware?
« on: May 16, 2015, 01:02 AM »
Hello,

I am currently trying to find a way to backup photos from my old GB Camera to my PC. I figured I could use the EDGB to load the GB Camera ROM then use a second GB(C/A) and a Link cable to transfer over the photos from the GB Camera to the EDGB, then grab the savegame from the EDGB folder and drop it into a programm called GB Camera Dump.

I've actually managed to do that by setting the save RAM to YES manualy after l load the Camera ROM. However, the GB Camera has 128Kbyte (16x8kbyte) of SRAM, EDGB only allows us to allocate 32kbyte.

The result is that the Gameboy Camera ROM will not work correctly and sending photos over to the EDGB might send photos into nirvana instead of the actual SRAM. I've found that apparently the last 6 photos i transfer over are actually saved. I fell like this is somewhat risky, as we could potentially loose precious photos that we might not have saved anywhere else (see http://krikzz.com/forum/index.php?topic=2865.0 for an example), luckily I am doing my experiments on a secondary, non-vital GB Camera.

Now my question: is the 32Kbyte SRAM Limit an actual hardware limit (i.e. there's only 32kbyte of SRAM actually on the board) or if it is a software limit that was set because it was thought a bigger SRAM was not needed? If It's the latter, can we expect 128Kbyte SRAM Support in a future OS Update?

Regards

Sascha

EDIT: From the looks of it, there's actually a 1024Kbit RAM Chip attached to the board, which would equal the needed 128Kbyte. Is the chip solely used as SRAM or does it serve another purpose? I assume the EDGB OS itself uses part of that for keeping settings?
« Last Edit: May 16, 2015, 01:32 AM by Localhorst86 »

Offline saturnu

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Re: Is the EDGB limited to 32k SRAM by Hardware?
« Reply #1 on: May 16, 2015, 09:06 AM »
EDIT: From the looks of it, there's actually a 1024Kbit RAM Chip attached to the board, which would equal the needed 128Kbyte. Is the chip solely used as SRAM or does it serve another purpose? I assume the EDGB OS itself uses part of that for keeping settings?

it seems to be so:

In best case EDGB can offer 64KB, rest of memory reserved for OS
« Last Edit: May 16, 2015, 09:10 AM by saturnu »

Offline Localhorst86

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Re: Is the EDGB limited to 32k SRAM by Hardware?
« Reply #2 on: May 17, 2015, 11:50 PM »
Thanks,

well, that's too bad but I guess SRAM >32k is not very common so asking for upgraded hardware to support that is not very reasonable.

But then again, my idea works, it just requires patience and care (and making copies of the pictures before transferring them) so its still nice to be able to save the precious memories from my old GB Camera with tools I have readily available.