From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 21962 invoked by alias); 4 Jul 2005 01:01:13 -0000 Mailing-List: contact ecos-discuss-help@ecos.sourceware.org; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: ecos-discuss-owner@ecos.sourceware.org Received: (qmail 21915 invoked by uid 22791); 4 Jul 2005 01:01:07 -0000 Received: from smtpr6.alphanetworks.com (HELO smtpr6.alphanetworks.com) (210.202.42.130) by sourceware.org (qpsmtpd/0.30-dev) with ESMTP; Mon, 04 Jul 2005 01:01:07 +0000 Received: from stevencheng ([10.50.71.1]) by smtpr6.alphanetworks.com (Lotus Domino Release 6.5) with SMTP id 2005070409010366-6185 ; Mon, 4 Jul 2005 09:01:03 +0800 Message-ID: <000b01c58034$05ee5f90$016ffea9@stevencheng> From: "Steven_cheng" <05071@alphanetworks.com> To: "Andrew Lunn" Cc: "Andrew Lunn" , References: <01df01c57e22$1291cca0$016ffea9@stevencheng> <20050701124913.GK5563@lunn.ch> <000101c57ff2$07c6cf10$016ffea9@stevencheng> <20050703194145.GL8479@lunn.ch> Date: Mon, 04 Jul 2005 01:01:00 -0000 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="ISO-8859-1" Subject: Re: [ECOS] What is the different between "ROM" and "ROMRAM" in the Bootup type ?? X-SW-Source: 2005-07/txt/msg00033.txt.bz2 Dear Andrew, I see, I will try it. Thank you for your help very much. Steven Cheng ----- Original Message ----- From: "Andrew Lunn" To: "Steven_cheng" <05071@alphanetworks.com> Cc: "Andrew Lunn" ; Sent: Monday, July 04, 2005 3:41 AM Subject: Re: [ECOS] What is the different between "ROM" and "ROMRAM" in the Bootup type ?? > On Sun, Jul 03, 2005 at 09:41:27AM +0800, Steven_cheng wrote: > > Dear Andrew, > > > > Thank you for you reply, but I still confuse about the following > > questions. > > > > 1) When the board powers on, does the CPU need to know which type and > > vendor of ROM flash?? (ex. AMD 29LV040B) > > No. It should be able to read from any type/vendor. You only need to > know more when you come to erase/write. But its not the CPU that does > what, its you application program. > > > > 2) How does the CPU know the memory address which the ROM locates ?? > > It is hardwired. Read the data sheet for your processor and look at > the schematics to see what chip select it is using. > > Andrew -- Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss