Re: speed of writing file is fixed when changing the CLK of SD/MMC



On Feb 5, 8:33=A0pm, "bobo" <beyondsa...@xxxxxxx> wrote:
Hello All,
=A0 =A0 I met a strange problem :
=A0 =A0 the speed of writing file is fixed to a same value (about
50KB/s)
whatever the SD/MMC CLK (from 600KHz to 12MHz), my platform is LPC2478,
S=
D

Assuming your code actually does what you think it does, this suggests
that the time spent transferring data to/from the card over the serial
interface is buried in the time the card's controller requires for
erasing/rewriting data.


Hi larwe, shall i erase pages before write it ? but the SD/MMC needn't this
operation, the controller int the SD/MMC card will do this automaticly, if
you erase the page manually, what's the difference ? can you give some
explanation of my problem ?

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