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doc:appunti:hardware:gps_logger_i_blue_747 [2019/10/10 22:46] – [Week Rollover Bug] niccolodoc:appunti:hardware:gps_logger_i_blue_747 [2019/10/10 22:47] – [Week Rollover Bug] niccolo
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 Actually I have two i-Blue 747 GPS data loggers. The older one is a **Model ID 001B**, which has already manifested the problem: today is **2019-10-10**, but GPX points logged have a timestamp of **2000-02-24**. If you do the math, you can find that there is a **difference of exactly 1024 weeks**. This means that the device internally stores timestamps using a **week counter of only 10 bits**. So exactly 1024 weeks after its //EPOCH// (the begin of the time it can handle), the timestamps rolls-back of that amount of time. Actually I have two i-Blue 747 GPS data loggers. The older one is a **Model ID 001B**, which has already manifested the problem: today is **2019-10-10**, but GPX points logged have a timestamp of **2000-02-24**. If you do the math, you can find that there is a **difference of exactly 1024 weeks**. This means that the device internally stores timestamps using a **week counter of only 10 bits**. So exactly 1024 weeks after its //EPOCH// (the begin of the time it can handle), the timestamps rolls-back of that amount of time.
  
-The other logger of mine is a **Model ID 001D**, which instead is still recording corrected timestamps today. I suspect that the week counter is nevertheless 10 bits, and just the hard-coded EPOCH is more recent. So the bug is **just to come in the near future**.+The other logger of mine is a **Model ID 001D**, which instead is still recording correct timestamps today. I suspect that the week counter is nevertheless 10 bits, and just the hard-coded EPOCH is more recent. So the bug is **just to come in the near future**.
 ===== Credits ===== ===== Credits =====
  
doc/appunti/hardware/gps_logger_i_blue_747.txt · Last modified: 2019/10/11 17:47 by niccolo