R4 MicroSD Slot Qs

Discussion in 'R4 DS' started by rhyguy, Sep 18, 2007.

  1. rhyguy
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    rhyguy GBAtemp Maniac

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    If you put a microsdhc with the kernel on it, and in the r4, would the r4 recognise thats the card is in there, and attempt to read it, but its all scrambled because of the different formatting?
     
  2. Kellicros

    Kellicros GBAtemp Fan

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    R4 doesn't support SDHC cards.
     
  3. rhyguy
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    rhyguy GBAtemp Maniac

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    I know that, but is it because it cant read anything all together, or because of the different format, everything is all scrambled up
     
  4. bfoos

    bfoos GBAtemp Fan

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    It's because of the different format. R4 doesn't know how to interpret data from SDHC cards. It may be a hardware limitation, or it may be software.
     
  5. SkH

    SkH GBAtemp Maniac

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    Well it's most definately the basic software inside every R4 that try reading the card for the FirmWare.
     
  6. bfoos

    bfoos GBAtemp Fan

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    Yes, it may be the actual firmware of the cart, which is not upgradeable.
     
  7. TLSpartan

    TLSpartan Kills threads

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    It is the actual firmware of the PIC inside the cart. You could re program it but that require highly advanced desoldering skills, to get it out of the R4. You would then need to write code to it to support SDHC reading and writing. Then you would have to solder it back in. Or you could just buy a DSLink or a CycloEvo and save yourself alot of trouble [​IMG] .
     
  8. Maikel Steneker

    Maikel Steneker M3 Fanboy

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    I still wonder... Wouldn't it be possible to format your SDHC-card in a special way so the R4 can read it and load a driver for SDHC? The driver could be in the first few bytes, which may be the same for SD and SDHC.
     
  9. striderx

    striderx GBAtemp Regular

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    Not at all likely... SDHC isn't a "driver thing." It's a hardware incompatibility. The R4 is ignorant to the ways of SDHC.

    strider
     
  10. Maikel Steneker

    Maikel Steneker M3 Fanboy

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    Oh... So... That's means that, for example, loading the thing-that's- not-a-driver from a normal SD-card and then loading an SDHC-card won't work either?
     
  11. Rayder

    Rayder Mostly lurking lately....

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    The R4 would have to support SDHC in hardware to be able to read anything from an SDHC card. Even if it was possible (which it isn't) to put some driver data on an SDHC card to make the R4 read SDHC cards, it still wouldn't work because the R4 can't see any of the data on the SDHC card. SDHC cards use a different method of arranging data on the card and it REQUIRES that the hardware knows how to access it.

    If the R4DS was hardware flashable, then it would be no problem to add SDHC compatibility, but it's not hardware flashable. The R4 uses "software" firmware loaders, not a hardware flash to update the firmware. When you update the firmware on an R4DS, you just changed some files on the microSD and the "firmware" is just the first data it reads from the microSD when you boot the R4. It does not actually make any changes in the R4DS itself when you change firmware loaders. The R4's hardware is not flashable....it never changes, so there is no way to add SDHC compatibility to the current version of the R4DS.

    Possibly, in the future, the R4 team will release a revised R4 that does support SDHC, or is hardware flashable, but the current design just cannot read SDHC cards, no matter how much we would like it to. I believe the fact that it can't support SDHC will be the R4's eventual downfall.

    I'd love to have more than 2gigs available instantly on my R4 too, but it just ain't gonna happen in the current revision.