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Old Jun 19, 2011, 11:29 AM
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Originally Posted by pät View Post
Does #11 use variable speeds for different cards? I think it's difficult to find out...Patrick
Hi Patrick, a 'standard' microSDHC card has a maximum RW current consumption of 60ma to 80ma.
See this link and click on the 'Technical Data' tab :
As for bus speed, I can only tell you that #11's clock frequency is 12Mhz. Obviously, the bus speed can't possibly be any higher than this.
The only way to check the data bus speed for definate, is to get a fq counter / scope on pin 5 of the card (clock).
If you can somehow interrupt pin 4 to the card (+ve supply), you could monitor the current consumption of the card in circuit, while it was reading and writing. If you have a 'duff' microSD card lying about and a spare microSD socket, it shouldn't be too hard to knock up an external card slot, allowing easy access to all 8 lines.

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