From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from snark.thyrsus.com (static-71-162-243-5.phlapa.fios.verizon.net [71.162.243.5]) by huchra.bufferbloat.net (Postfix) with ESMTP id EF4F4200890 for ; Tue, 13 Mar 2012 22:00:37 -0700 (PDT) Received: by snark.thyrsus.com (Postfix, from userid 1000) id 564EE40617; Wed, 14 Mar 2012 01:00:19 -0400 (EDT) Date: Wed, 14 Mar 2012 01:00:19 -0400 From: "Eric S. Raymond" To: Patrick Maupin Message-ID: <20120314050019.GA26429@thyrsus.com> References: <20120313230612.GA24800@thyrsus.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: Eric Conspiracy Secret Labs X-Eric-Conspiracy: There is no conspiracy User-Agent: Mutt/1.5.21 (2010-09-15) Cc: thumbgps-devel@lists.bufferbloat.net, tz Subject: Re: [Thumbgps-devel] Project clarification X-BeenThere: thumbgps-devel@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list Reply-To: esr@thyrsus.com List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 14 Mar 2012 05:00:38 -0000 Patrick Maupin : > If we really want to consider our own firmware, we might consider > something like nuttx running on either an Atmel part or an NXP > LPC3131. Olimex has an NXP development board for $90. Let's do the simple thing first. If we can pull accuracy down to around 1-2ms without custom firmware - which I think is achievable - I don't think the extra NRE for custom firmware can be justified. OTOH, that route starts to look more attractive if the Mark I thumbGPS works and we start thinking more seriously about a Mark II device with Dave's environmental sensors on it. What each of you with a differing speculative design (or family of designs) ought to do is name it so we can avoid confusing each other in discussion. I hereby claim the name "Plain Jane" for the concept where we build a straight-up USB thumb with PPS, using a commodity GPS module with TTL serial outlet mated to a PL2303 or similar commodity USB-to-serial converter, no custom firmware. -- Eric S. Raymond