From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pigeon.gentoo.org ([69.77.167.62] helo=lists.gentoo.org) by finch.gentoo.org with esmtp (Exim 4.60) (envelope-from ) id 1KqZ3M-0004jZ-QP for garchives@archives.gentoo.org; Thu, 16 Oct 2008 20:02:37 +0000 Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 98374E03AC; Thu, 16 Oct 2008 20:02:34 +0000 (UTC) Received: from hrndva-omtalb.mail.rr.com (hrndva-omtalb.mail.rr.com [71.74.56.123]) by pigeon.gentoo.org (Postfix) with ESMTP id 26ABDE03AC for ; Thu, 16 Oct 2008 20:02:34 +0000 (UTC) Received: from [192.168.2.30] (really [24.73.161.102]) by hrndva-omta06.mail.rr.com with ESMTP id <20081016200232.JBXS13620.hrndva-omta06.mail.rr.com@[192.168.2.30]>; Thu, 16 Oct 2008 20:02:32 +0000 Message-ID: <48F79DDE.6060307@tampabay.rr.com> Date: Thu, 16 Oct 2008 16:02:38 -0400 From: wireless User-Agent: Mozilla/5.0 (X11; U; Linux i686 (x86_64); en-US; rv:1.8.1.17) Gecko/20080829 SeaMonkey/1.1.12 Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-embedded@lists.gentoo.org Reply-to: gentoo-embedded@lists.gentoo.org MIME-Version: 1.0 To: gentoo-embedded@lists.gentoo.org Subject: Re: [gentoo-embedded] Documentation for embedded linux beginer References: <8349216a0810160615u6af15d1i3496339975be6489@mail.gmail.com> In-Reply-To: <8349216a0810160615u6af15d1i3496339975be6489@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Archives-Salt: 4ea2c84c-af6e-4ac3-8675-6bbb895b7e00 X-Archives-Hash: 20f3a17d5385c33d255a5f528895e5ee Jean-Marc Beaune wrote: > I tried several times to start with embedded linux but can't really > figure out how to start in a proper way. It's really quite simple. Choose a simple problem to solve that requires an embedded system. Running a large database and sending out packets, is not a valid reason. Why? Because you can use a server for that purpose. Now minimizing that server to fit into an airplane, so it is as light-weight and low power as possible, is a valid reason to build an embedded system. Choose an OS (embedded linux cause it's the coolest and has too many readily available software resources). Embedded linux is not the same thing as embedded (gentoo) linux! Caveat Emptor! Take one sheet of paper and specific the hardware resources you need to solve that problem: Micro controller (decision making capability based on software) A/D analog (input/output) digital converters ? DIO digital input/output usb special sensors such as temperature, pressure, acceleration..... flash amount/types of memory ethernet (or 2) etc etc (you make the list) Folks on this list will help you with identifying and solving your problem. Choose a processor/arch that readily solves your design constraints but has enough computation resources to run embedded linux and to solve your problem, too. Here is where you ask the list for architecture recommendations for example. If your problem requires low power, so as to run off of batteries or a solar panel, then that will affect your selection of processor. Different processors use vastly different amounts of energy. Low power is but one dimension of processor selection. If you just want to noodle in the office, you may want to choose a processor that comes on a SBC (single board computer) such as mini-itx form factor or one of the epia boards and an x86 arch, so it is closest to what you want, and most familiar (arch) to what you have used. You can look at the various arch's supported by gentoo embedded, as that will quickly 'skinny down' your selection. You can even visit various vendor web sites to look through a myriad of boards (SBC) that the various vendors offer. Then ask on this list to see what others have done, so you can leverage their knowledge and get a SBC (embedded gentoo linux board) that is familiar to persons on this list. That way help is easy to find. Maybe you should start by reading the list archives to see what other (embedded) noobs have chosen to begin their quest? Alternatively, maybe GNAP is ready for noobs to once again build a simple firewall on an old x(4)86 box as their first exposure to embedded (gentoo) linux. Make sure there is a 'body of work' within embedded gentoo for the processor/SBC you choose, if you want the least painful path towards your quest(goal) of solving the problem you defined above. A firewall is a nice project, because it's very likely to be something that you use and maintain. Choose your problem, wisely. GNAP is a very inexpensive introduction to embedded gentoo, as most folks have old pc hardware just laying around. Building an embedded system that is part of an aimless wandering experience, most often leads to failure and abandonment. If you build something that you want and will use to solve a problem, then you will be hooked and will be well on your way to becoming an embedded systems develop, imho. Embedded systems are spartan (hard and minimalistic) ventures that are best employed to solve narrowly focused problems. That's the justification for not using a server or workstation to solve the same problem. ymmv, James