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Author Topic: Cheap small capacity SD Cards?  (Read 1643 times)
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Washington
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Maybe it doesn't comply with the recommended interrogation sequence?  There's a flowchart in the SD specs showing you how to properly differentiate.  It's backward compatible.  If you (as a designer) just initialize and go, instead of probing and verifying behavior, you may end up using the wrong command set.  Just a guess.
So it is not really backwards compatible... If the device is not aware of SDHC than it will fail.
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Uh... yeah, OK.  Point taken.  I guess I was looking at it the other way around.  An SDHC-compatible reader must... as in, per the spec, absolutely must... know how to tell the difference between SDHC, SD, and MMC cards.  But you're right, there's no guarantee that a new card would work in an old reader that's not aware of fixed block addressing and whatnot.
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Washington
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Uh... yeah, OK.  Point taken.  I guess I was looking at it the other way around.  An SDHC-compatible reader must... as in, per the spec, absolutely must... know how to tell the difference between SDHC, SD, and MMC cards.  But you're right, there's no guarantee that a new card would work in an old reader that's not aware of fixed block addressing and whatnot.
Thats the problem I have. Lots of old devices.
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Avoid throwing electronics out as you or someone else might need them for parts or use.
Solid state rectifiers are the only REAL rectifiers.
Resistors for LEDS!

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