DataLogger IOT 9DOF

Sensors IMU & Motion
1

Some suggestions/reccos:

  1. The firmware appears to go unstable when requesting fast logging times (Set log time of board to 10 or 50 msec and the board throws an error):

Here is the startup showing my configuration. Note that I was trying to push the board at 10 msec, but it was achieving something closer to 20 msec/line (I bumped serial rate to 230,400 bps to make sure serial wasn’t bottlenecking thruput):

SparkFun DataLogger IoT - 9DOF   (c) 2023 SparkFun Electronics

Version: 01.00.02  - build 000098





[W] GNSS::isConnected no traffic seen (first attempt)

[I] Restoring System Settings ...restored from ESP32 Preferences

[E] WiFi: No credentials provided. Unable to connect

[W] [Startup] WiFi Network failed to initialize.

[I] Loading devices ... 3 devices detected

    MAX17048              - MAX17048 LiPo Battery Fuel Gauge  {qwiic}

    ISM330                - ISM330 Inertial Measurement Unit  {SPI}

    MMC5983               - MMC5983 Magnetometer  {SPI}



[I]  Time:	2023-07-07T03:42:48

[I]  Uptime:	0 days, 00:00:04.517

[I]  External Time Source: NTP Client

[I]  Board Name: SparkFun DataLogger IoT - 9DoF

[I]  Board ID: SFD1DCC4B886E694

[I]  SD card not available

[I]  WiFi - Not Connected

[I]  Battery - Not Connected

[I]  System Deep Sleep: disabled

     Sleep Interval:  0 seconds

     Wake Interval:   0 seconds



[I]  Logging Interval (ms): 10

[I]  Serial Output:  CSV Format

     Baud Rate:  230400

[I]  SD Card Output: Disabled

     Rotate Period: 	24 Hours



[I]  IoT Services:

     MQTT Client           : disabled

     MQTT Secure Client    : disabled

     HTTP IoT              : disabled

     AWS IoT               : disabled

     Azure IoT             : disabled

     ThingSpeak MQTT       : disabled

     MachineChat           : disabled



[I]  Connected Devices [3]:

     MAX17048              - MAX17048 LiPo Battery Fuel Gauge  {qwiic}

     ISM330                - ISM330 Inertial Measurement Unit  {SPI}

     MMC5983               - MMC5983 Magnetometer  {SPI}





Content-Type: text/csv



General.Time,MAX17048.Voltage (V),MAX17048.State Of Charge (%),MAX17048.Change Rate (%/hr),ISM330.Accel X (milli-g),ISM330.Accel Y (milli-g),ISM330.Accel Z (milli-g),ISM330.Gyro X (milli-dps),ISM330.Gyro Y (milli-dps),ISM330.Gyro Z (milli-dps),ISM330.Temperature (C),MMC5983.X Field (Gauss),MMC5983.Y Field (Gauss),MMC5983.Z Field (Gauss)

4561,4.909,199.227,-4.160,-10.858,-110.776,1018.700,332.500,-227.500,-297.500,24.875,0.22064,0.18378,0.36536

4598,4.909,199.227,-4.160,-10.980,-110.776,1018.700,262.500,-350.000,-280.000,24.816,0.22168,0.18420,0.36615

4618,4.909,199.227,-4.160,-10.980,-110.776,1018.700,262.500,-297.500,-332.500,24.859,0.22144,0.18427,0.36597

<Redacted for brevity here>

5959,4.904,199.227,-4.160,-10.858,-111.020,1018.700,192.500,-262.500,-385.000,24.809,0.22083,0.18433,0.36627

5979,4.904,199.227,-4.160,-10.858,-110.898,1018.578,210.000,-315.000,-332.500,24.797,0.22101,0.18427,0.36597

5999,4.904,199.227,-4.160,-10.736,-110.898,1018.578,175.000,-262.500,-350.000,24.789,0.22089,0.18457,0.36615

6019,4.904,199.227,-4.160,-10.858,-110.898,1018.700,262.500,-210.000,-315.000,24.781,0.22119,0.18475,0.36566

Guru Meditation Error: Core  1 panic'ed (LoadProhibited). Exception was unhandled.



Core  1 register dump:

PC      : 0x4020f94a  PS      : 0x00060530  A0      : 0x800edddf  A1      : 0x3ffb2250  

A2      : 0x00000000  A3      : 0x3ffcab10  A4      : 0x3ffb96e0  A5      : 0x000000ff  

A6      : 0x3ffb9714  A7      : 0x003fffff  A8      : 0x8020f950  A9      : 0x3ffb2230  

A10     : 0x3ffc5548  A11     : 0x3ffc5470  A12     : 0x3ffc5170  A13     : 0x3ffca0c8  

A14     : 0x3ffb8a6c  A15     : 0x3ffbd5c4  SAR     : 0x0000000c  EXCCAUSE: 0x0000001c  

EXCVADDR: 0x0000011b  LBEG    : 0x40085619  LEND    : 0x40085621  LCOUNT  : 0x00000027  



Backtrace: 0x4020f947:0x3ffb2250 0x400edddc:0x3ffb2270 0x4014bdcd:0x3ffb2290



ELF file SHA256: d4c9f2bcdbeb828a

Note the above is from me requesting 10 msec logging, but actually getting about 20 msec. I still get the error when I try to log at 50 msec time steps, which per the above example shouldn’t be stressing the board.

Note the failure does appear to be coupled to a set amount of time after logging resumes. If I slow down the logging rate, the board survives a proportional amount of time longer before it faults. I always had it crash less than 20 seconds from logging resumption in my testing.

  1. Recommendation for enhancement: It sure would be nice to have an option to put out the ISO8601 time with fractional seconds, in order to avoid having to reconstruct it from the bottom three digits (msecs) of the TOW GPS field. This is a legal ISO8601 option, in which the lowest time parameter (in this case seconds) is allowed to have a set number of fractional seconds ("A decimal fraction may be added to the lowest order time element present in any of these representations. A decimal mark, either a comma or a dot, is used as a separator between the time element and its fraction". Since this is my recco, I vote for the dot!).

Not having fractional seconds doesn’t limit the utility of the board, but if you’re trying to make it easier to use, I’d much rather have a single time field than having to kludge them together after the fact

2

It is definitely coupled to the logging period. 100 msecs works; 10 or 50 do not. The problem is that running the imu at 10 Hz is pretty coarse if you actually want to do applications with it (100 Hz is significantly more useful).

Found a third thing: In the hookup guide, I think you mean to say the max baud rate is 500,000 (possibly 5,000,000?) not 50,000 (since it’s default data rate as shipped as 115;200 bps).