Acknowledgements This work was supported by Hiroyuki Ito and Korkut Kaan Tokgoz at Tokyo Institute of Technology and Kenichi Takeda at Shinshu University. Overview Available in Arduino development environment. Data logger for Sony's IoT development board SPRESENSE. The function of this data logger is to write inertia sensor data along with time stamp. Time stamp data is corrected with GPS signal. Features * After creating a new file, Real Time Clock (RTC) is corrected with the GPS signal before data logging. * Data logging will not start until the RTC is corrected using the GPS signal. * When the time is corrected, the GPS reception process stops. The GPS reception process will sleep until the next time recording remains accurate within adjustments. * Acceleratia and pressure data are recorded with 20[ms] time intervals. * The data is stored in the SD card slot of CXD5602PWBEXT1. * Compatibility with QZSS Michibiki. * A new file is created every 30 minutes. * Does not drive interrupts. * The acceleration range is ± 4 [G] and the resolution is 1 [mG]. * The unit of air pressure resolution is 1 [hPa]. Disclaimer * This software is MIT license. Copyright (c) 2019 TechnoPro, Inc. TechnoPro Design Company Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. * We cannot respond to inquiries. State transition The status of LEDs are shown below. The software performs state transition State Meaning LED3 LED2 LED1 LED0 eStateIdle System idle state off off on blinking eStateSetup Setup state off on off off eStateRenewFile File update state off on on blinking eStateGnss GPS time data correction state on off off blinking eStateSensor Sensor data acquisition state on off on blinking eStateError Error occurred on on off hold eStateWriteError Write error occurred on on on hold Data format The data stored on the SD card is in the following format. | Format version | Terminal number(*1) | YYYY/MM/DD hh:mm:ss.ss | Serial number | Time interval[ms] | Acc-X[G] | Acc-Y[G] | Acc-Z[G] | Barometric pressure[hPa] | (*1)The meaning of the record. You can edit on the source code. Requirements **Devices** * SPRESENSE+CXD5602PWBEXT1 https://developer.sony.com/develop/spresense/ * SPRESENSE-SENSOR-EVK-701 https://www.rohm.co.jp/support/spresense-add-on-board **Source of code** * spresense-arduino-compatible https://github.com/sonydevworld/spresense-arduino-compatible The referenced sample is as follows. ./Arduino15/packages/SPRESENSE/hardware/spresense/1.0.0/libraries/GNSS/examples/gnss_tracker * /gnss_file.h/gnss_file.cpp/gnss_nmea.h/gnss_nmea.cpp/gnss_tracker.h * SPRESENSE-SENSOR-EVK-701 https://github.com/RohmSemiconductor/Arduino The referenced sample is as follows. * /BM1383AGLV.h/BM1383AGLV.cpp/KX122.h/KX122.cpp * The code created for this project is as follows. * /cow_log.h/sd_acc_press_gps.ino How to use 1. Set up SPRESENSE Arduino IDE is as follows. https://developer.sony.com/develop/spresense/ 1. Connect CXD5602PWBEXT1 and SPRESENSE-SENSOR-EVK-701 to SPRESENSE. 1. Connect the SD card to CXD5602PWBEXT1. 1. When the power is turned on, the device starts up, the time is corrected by GPS, and the log is saved on the SD card. 1. Turn off the power and remove the SD card. Reference website * Try Spresense's GNSS (GPS) reception function https://y2lab.org/blog/gudget/trying-gnss-receiving-function-on-spresence-7497/ * Play with RaspBerry Pi http://nopnop2002.webcrow.jp/ Tools * Tera Term Home Page https://ttssh2.osdn.jp/