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 34682200890 for ; Wed, 14 Mar 2012 05:23:56 -0700 (PDT) Received: by snark.thyrsus.com (Postfix, from userid 1000) id 80BFD40617; Wed, 14 Mar 2012 08:23:36 -0400 (EDT) From: esr@thyrsus.com (Eric S. Raymond) To: thumbgps-devel@lists.bufferbloat.net Message-Id: <20120314122336.80BFD40617@snark.thyrsus.com> Date: Wed, 14 Mar 2012 08:23:36 -0400 (EDT) Subject: [Thumbgps-devel] GPS dongles X-BeenThere: thumbgps-devel@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 14 Mar 2012 12:23:56 -0000 Chinavision CVGI-B07: $23 This is the one with the unidentifiable 8-pin PL2303 clone, no good because it probably doesn't pass 1PPS and we don't know how to get the parts for a clone, Canmore GT-730F(L): $36 Based on the SkyTraq Venus 5 chipset. Claims 65 channels. The "datasheet" at the vendor site is a profoundly uninformative user manual - can't tell what USB-to-serial chip it's using. However Amazon claims it's Linux-compatible. GlobalSat ND-100S USB GPS Dongle: $32 SiRF-III-based. Claims Linux compatibility. Uses the PL2303 driver (the documentation is silent on this but if you download the Linux driver it has pl2303 in the archive name). This looks like a good target for blue-wiring or cloning; we should take one apart to see if it has a real PL2303 in it. My guess is it will; GlobalSat is not a fly-by-night outfit. SJ-5282 GPS Dongle: $25 Based on SkyTraq Venus 6. No data sheet at the vendor site. Will inquire at service@sja.com.tw. The enclosure looks familiar, I think this one is sold under multiple names. MightyGPS 100ND: $52 Uses a GPS chipset called "M-Star MSB2122" not known to me. No datasheet at the vendor site. USB adapter not specified. I'll email info@mightygps.com to ask. uBlox 5 USB GPS stick Seen at http://www.laptopgpsworld.com. Listed for completeness; probably uses the on-board uBlox USB that doesn't carry 1PPS out. NaviLock NL-464US SiRF 3: Not for sale in US Uses SiRF-III. Can't identify the adapter, but it claims Linux 2.6 compatibility. GiSTEQ GPS USB dongle: $39 Can't identify either GPs or adapter. Gotop GPS USB Dongle: $24.50 Uses PL2303. No datasheet available at vendor site. Here's the alibaba page listing Chinese products of this type: http://www.alibaba.com/showroom/usb-gps-dongle.html It looks like there are a handful of designs being resold under a lot of different names - the Chinavision and SJ-5282 in particular are all over the place. I think our best teardown target is probably the GlobalSat ND-100S, but I'm going to use the alibaba page to shotgun the Chinese vendors looking for (a) any that might carry PPS, and (b) what the chipsets and USB adapters are. -- Eric S. Raymond Ideology, politics and journalism, which luxuriate in failure, are impotent in the face of hope and joy. -- P. J. O'Rourke