Artemis Openlog serial not logging

Artemis Openlog V2.4 unit sees GPS data over Qwiic, clean reliable at 19200
e.g.
07/01/2025,17:54:11.39,07/01/2025,21:54:08.000,438907452,-699731690,6221,22,3,125,2175055,107,

07/01/2025,17:54:12.40,07/01/2025,21:54:09.000,438907440,-699731693,6396,21,3,17,2175055,118,

07/01/2025,17:54:13.40,07/01/2025,21:54:10.000,438907433,-699731688,6340,22,3,79,2175055,109,

But: For a clean 3.3v 19200 baud data stream from Omnipresense OPS243-A radar sensor, into Artemic Openlog Rx pin, GND connected, clean data pulled high, zeroes bits: Errors when attempting to scan with Rx pin connected (3.3v pulled high from OPS243-A):

++ MbedOS Error Info ++

Error Status: 0x80FF0144 Code: 324 Module: 255
Error Message: Assertion failed: handle != NULL
Location: 0x49DBD
File: mbed-os/targets/TARGET_Ambiq_Micro/TARGET_Apollo3/device/serial_api.c+411
Error Value: 0x0
Current Thread: main Id: 0x10007E4C Entry: 0x4AF11 StackSize: 0x1000 StackMem: 0x10006E28 SP: 0x1005FEEC
For more info, visit: mbedos-error

– MbedOS Error Info –

any thoughts or suggestions?

Does it work if you power the OLA first, then hookup the radar? I’m wondering if the radar is trying to use the bus too early

If you have a scope it might be worth verifying everything is behaving as expected as well

Finally, it might be related to the issue mentioned in v2.7 here…you can upgrade FW as so using the upload GUI :smiley:

Thanks!! Firmware updated 2.10, running fine. Getting serial echoed back out Tx, looks good. Test of Tx-echo without writes to SD. Will look at SD writes tomorrow.

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OLA SERIAL STILL NOT LOGGING: Ok tried a fresh 8GB SD card formatted with SD Memory Card Formatter for Windows/Mac - SD Association - logging the GPS data to SD card, data look good. Dir entry:
2025-07-02 16:59 22608 dataLog00002.TXT

Serial data from OPS243-A radar: Menu setup-
Menu: Configure Serial Logging

  1. Log serial data: Enabled, analog logging on RX/A13 pin disabled
  2. Output serial data to TX pin: Enabled, analog logging on TX/A12 pin disabled
  3. zmodem start delay: 20 seconds
  4. Set serial baud rate: 19200 bps
  5. Add RTC timestamp when token is received: Enabled
  6. Timestamp token: 10 (Decimal) = Line Feed
    x) Exit

The 3.3V serial data on OLA Rx pin is echoed properly to OLA Tx pin. I’m providing hand gestures to the OPS243-A, and its serial-out packets are showing up perfectly via Picoscope on Tx and separately packets are showing up via MQTT local wifi. But OLA SD card serial data file is empty.
Root Directory Listing:
2025-07-02 17:01 1528 OLA_settings.txt
2025-01-01 00:00 553614 dataLog00000.TXT
2025-07-02 17:03 0 serialLog00000.TXT
2025-07-02 17:01 501 OLA_deviceSettings.txt
2025-01-01 00:00 10614 dataLog00001.TXT
2025-07-02 17:03 34036 dataLog00002.TXT
End of Directory

So interested in any suggestions to get the serial Rx data writes to SD card file- thanks!

To be clear, just the serialLog00000.txt is the issue?

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Well first time trying the OLA as a serial datalogger- I’m assuming the serial data incoming on Rx pin are stored in the serialLognnnnn.TXT files - do I get that right? So far, nothing being stored in serialLognnnnn.TXT file(s). GPS data being stored perfectly in the dataLognnnnn.TXT files, so it doesn’t look like an SD card issue.

Hi @rwrand ,

It looks like you are doing everything correctly. I’m puzzled why the serialLog files are empty.

Your “Getting serial echoed back out Tx” and “The 3.3V serial data on OLA Rx pin is echoed properly to OLA Tx pin” comments are confusing. That should never happen. The “Output serial data to TX pin” option allows the ‘sensor’ data (GNSS data in your case) to be output on the Tx pin. Looking at the firmware, there is no link from RX data (Serial1.read) to TX data (Serial1.print). RX data should only go to the SD card serialLog. Only sensor data should go to the TX pin. If your comments are accurate, it suggests you have a short of some kind on the TX and RX pins?

Other thoughts - somewhat random:

You are storing GNSS data in the dataLog files. What log interval have you selected? It looks like 1 second? That is very modest and shouldn’t be causing any problems. Are you logging anything else to the dataLog files? I’m wondering if the firmware is busy logging ‘sensor’ data to SD and that the serial is being ignored. It’s very odd that the serialLog files are completely empty. I’d expect there to be something in them at least.

Perhaps try disabling the “Log to microSD” option, so that the dataLog is as idle as possible. Do the serialLog files start to contain data?

Maybe the “Output serial data to TX pin” is causing problems. If you disable that, do the serialLog files start to contain data?

I hope this helps,
Paul

I put a 15v,100uF electrolytic cap across GND and 3.3V which eliminated issues on reset/powerup with SD card inserted

Tried disabling GPS datalogging
Menu: Configure u-blox GPS Receiver
1) Sensor Logging: Disabled
x) Exit
and disabling Output serial data to TX pin
Menu: Configure Serial Logging
1) Log serial data: Enabled, analog logging on RX/A13 pin disabled
2) Output serial data to TX pin: Disabled
3) zmodem start delay: 20 seconds
4) Set serial baud rate: 19200 bps
5) Add RTC timestamp when token is received: Enabled
6) Timestamp token: 10 (Decimal) = Line Feed
x) Exit
- no improvement.

Root Directory Listing:
2025-07-04 10:03 1528 OLA_settings.txt
2025-01-01 00:00 553614 dataLog00000.TXT
2025-07-04 10:04 0 serialLog00000.TXT
2025-07-04 10:03 501 OLA_deviceSettings.txt
2025-01-01 00:00 10614 dataLog00001.TXT
2025-07-02 22:36 2035401 dataLog00002.TXT
2025-01-01 00:00 1734 dataLog00003.TXT
2025-07-04 10:04 15945 dataLog00004.TXT
End of Directory

OK, but:

Your “Getting serial echoed back out Tx” and “The 3.3V serial data on OLA Rx pin is echoed properly to OLA Tx pin” comments are confusing. That should never happen. The “Output serial data to TX pin” option allows the ‘sensor’ data (GNSS data in your case) to be output on the Tx pin. Looking at the firmware, there is no link from RX data (Serial1.read) to TX data (Serial1.print). RX data should only go to the SD card serialLog. Only sensor data should go to the TX pin. If your comments are accurate, it suggests you have a short of some kind on the TX and RX pins?

Understood- sorry for the confusion. I had test wires switched. No short on Tx and Tx.

Serial logging working! And, OLA is storing an RTC tag before each serial data chunk.

Is there any way to output the serial data (not GPS, the serial data) to the terminal?

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Hi @rwrand ,

Thanks for the update. I’m glad you got it working.

Sorry, no, the OLA firmware does not support echoing incoming serial data to the terminal.

Best wishes,
Paul