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Re: trivial question about cpu thumb mode
- From: Jonathan Larmour <jifl at eCosCentric dot com>
- To: rakesh <mljangir at yahoo dot co dot in>
- Cc: ecos-discuss at sources dot redhat dot com
- Date: Tue, 02 Sep 2003 04:27:14 +0100
- Subject: Re: [ECOS] trivial question about cpu thumb mode
- References: <20030827060132.44467.qmail@web8001.mail.in.yahoo.com>
rakesh wrote:
I have a very basic question about cpu thumbe mode.
What is cpu thumb mode operation? And how it's
behaviour is changed in thumb mode?
You need a book about the ARM architecture. I believe:
http://www.amazon.co.uk/exec/obidos/ASIN/0201737191
is generally recommended as the canonical text, although there's also:
http://www.amazon.co.uk/exec/obidos/ASIN/0201675196
and
http://www.amazon.co.uk/exec/obidos/ASIN/0201624109
In summary, thumb is an instruction set with opcodes 16 bits wide instead
of the usual 32 bits. Various ARM processors support thumb mode.
Jifl
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