A.M. 12 miles total. Rob and Caleb joined us. Benjamin did 8, Jenny 3, Julia 1, Joseph 1, Jacob 1, William 0.5. Benjamin, Caleb, and I did a pickup for 1 K in 3:14 down the canyon. Caleb had Garmin Forerunner 610, so we had a chance to test it against the Fast Running Friend. Total distance in reality was 8.00 and that is what FR 610 reported. Fast Running Friend said 7.99. However, FR 610 won hands down on immediate pace, which surprised me. It sampled it every second, and every single time got it right on - verified against land marks. Fast Running Friend was OK, but it sampled every 0.08-0.15 miles, so the data came with delay. Even though we've got David fighting Goliath here - one hacker that rights code in his spare time vs a large business, I am still competitive when it comes to what matters to me - precision. Besides, when David vs Goliath analogy is used it is frequently forgotten that it was David who won. So I started researching. First we tested the position reported FR 610. When we stood in place it did not change - Fast Running Friend (working through Android and MotoACTV GPS receiver/driver) cannot stay still - it wiggles. To make sure that FR 610 was not playing tricks we moved a few feet. It changed. We went back to where we started. The position went back to what it was originally. So it was apparent that FR 610 had the upper hand on the position itself. I did some research and discovered that FR 610 uses SiRFstarIV chipset which has a lot of cool features including the ability to neutralize the noise. It was quite an adventure to figure out what GPS chipset was in MotoACTV. I knew it was some SiRF chip, otherwise Motorolla would not have named the driver SiRFDrv., but all of my diagnostic tricks as well as internet searches failed to unearth the info. I got really mad, replaced the driver in /etc/location.cfg with a dummy one to avoid unwanted restart of the real one, killed the driver, then manually turned on the GPS via /dev/gps_standby and dumped /dev/ttyS0. Downloaded the protocol description PDF for SiRFStarIII, and found an message that had an unsupported code. Then I found the manual for SiRFStartIV and sure enough that message was documented. So from this I think we can fairly safely assume that MotoACTV does have SiRFStarIV just like FR 610. The difference, it appears, is in the quality of the driver. It looks like while Garmin did a thorough job using all of the features of the hardware, Motorolla quickly put something together and threw it out on the market. Thus the difference in the quality of position reporting. This is correctable in Fast Running Friend, though. I can write the driver to match the one used by Garmin. This will be an adventure and a great learning experience.
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