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Re: Atmel AT26 SPI Flash
- From: William Wagner <will_wagner at carallon dot com>
- To: Chris Holgate <chris at zynaptic dot com>
- Cc: eCos Discussion <ecos-discuss at ecos dot sourceware dot org>
- Date: Wed, 21 Jul 2010 22:49:54 +0100
- Subject: Re: [ECOS] Atmel AT26 SPI Flash
- References: <4C474F72.6090908@carallon.com> <4C4757E6.2070204@zynaptic.com>
Hi Chris,
On 21/07/2010 21:26, Chris Holgate wrote:
Hi William,
William Wagner wrote:
I have a board with Atmel AT26 SPI flash chip on and am looking to write
a driver. Before I begin I thought I would check if anyone has already
done this. I see there is a driver for AT45 (dataflash) but
unfortunately the parts are not compatible and I'm not sure it's a great
starting point as they are quite different.
I'm not familiar with the AT26 series, but when I was writing the M25Pxx
driver I did notice that the M25 and AT25 parts shared the same
underlying protocol. However, I didn't add any AT25 parts to the
supported component list since I didn't have any to test the driver
against. If the AT26 shares the same protocol as the AT25/M25P parts,
you may be able to use the existing M25Pxx driver by just adding a
suitable device definition.
They are certainly similar, however there are some key differences. The
AT25 is the same except for a couple of erase commands being a different
address, otherwise they look very similar. The AT26 has exactly the same
commands, but a slightly different status register, and sectors are not
all the same size so locking is slightly different.
Overall I think they are sufficiently different for me to start a new
driver, using yours as a point to start from. I will then try to write a
driver that works for both AT25xxxx and AT26xxxx
Will
Chris.
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Will Wagner will_wagner@carallon.com
Development Manager Office Tel: +44 (0)20 7371 2032
Carallon Ltd, Studio G20, Shepherds Building, Rockley Rd, London W14 0DA
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