On Tuesday 20 February 2007 6:01 pm, Wolfgang Mües wrote:
> Hi NGZ,
>
> On Dienstag, 20. Februar 2007, NZG wrote:
> > They don't implement the CSD field READ_BL_LENGTH?
>
> Of course the CSD is implemented, and the READ_BL_LENGTH field is set to
> 1024 (!).
Ah, well then you know the block size when the board initializes. The 
bootloader just needs to be fixed to support the larger block or to use CMD16 
SET_BLOCKLEN to flip it to something supported.

> > If you a member of the consortium
>
> No. I'm not.
Yea me neither, I was hoping someone was who was could fuss about it ;-).

>
> > I would complain, they are claiming
> > this is an "SD" card right? That entails following certain rules.
> > I am assuming this isn't Sandisk or one of the major companies doing
> > this.
>
> _All_ are doing this. There is no other way to specify a 2 GByte card!
Makes sense,  was under the impression a rebel was selling something that 
wasn't detecting correctly.

> > Perhaps CMD16 SET_BLOCKLEN is implemented and can you set that to
> > change it to something reasonable?
>
> You don't need this. Why? Simple use 512 as blocklength.
I suppose that's possible, but then your software blocks won't match up with 
the blocks read from the device, why introduce the extra complexity if you 
don't have to?

You'll also transferring more information than required as a 512 read will 
require the transfer of twice that many bytes (not counting protocol 
overhead)

NZG
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