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 software performs state transition.
The status of LEDs are shown below.

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/
2. Connect CXD5602PWBEXT1 and SPRESENSE-SENSOR-EVK-701 to SPRESENSE.
3. Connect the SD card to CXD5602PWBEXT1.
4. 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.
5. 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/