Got a problem with a rns510 c,
i tried updated the firmware to 5218, it failed and wouldn't boot back to the old firmware, so i used a fix .iso image found on
http://gpsunderground.com/ but now it boots but is not usable
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now i am trying to get any firmware back on to make it usable (1100/3810) but the unit complains about invalid clamp state
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i have read i need to change the time on my dash from 24hr to 12 but i dont have highline clocks just the standard so i cant change the time format.
Any ideas what to do?