j3tstream wrote in to show off his Teensy GPS logger:
Issue encountered: On the first board prototype i have mounted a PA6B without problem, when i powered up the pcb for the first time the GPS try to lock to satellite, in this case the 3d fix output should continuously output one-second high-level with one-second low-level signal, in theorical, regarding the data sheet, when the GPS is locked on the satellite, the output pin should continuously output low-level signal, but in my case, the output give me a high level signal, probably du to the firmware, so i decided to re-upgrade with the default factory firmware, the software, firmware, and guideline are available here. Be careful, the factory firmware set the baud rate to 9600bps, not 4800.
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