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Flash Driver Read/Write Alignment Question
- From: Jay Foster <jay at systech dot com>
- To: "'ecos-discuss at ecos dot sourceware dot org'" <ecos-discuss at ecos dot sourceware dot org>
- Date: Fri, 9 Jun 2006 10:06:25 -0700
- Subject: [ECOS] Flash Driver Read/Write Alignment Question
I am puzzling over how the eCos flash drivers are supposed to work when
using 16-bit wide flash devices. I'm using an ARM architecture (ARM7TDMI,
ARM940T), and the AMD AM29LV160 flash device connected in the 16-bit wide
mode (CYGNUM_FLASH_WIDTH=16).
Looking at the flash driver code, this defines the flash_data_t as a 16-bit
type. This results in all accesses to the flash device to be performed as
16-bit reads/writes.
The flash driver defines some special addresses (FLASH_Setup_Addr1,
FLASH_Setup_Addr2, etc.). At least one of these will be defined as an odd
address. This will result in an unaligned transfer, causing a DATA ABORT
exception. What am I missing here?
Jay
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