It is not possible to use all the commands mentioned in UM2791 for VIC3DA

[HAO1]

Hi everyone,

I am having trouble with the Teoseo VIC3DA GNSS module:

My project is using the Teoseo VIC3DA to obtain information about GPS, gyroscope, and accelerometer, but in the default mode, I cannot see any data from the gyroscope or accelerometer. Therefore, I have tried sending the following commands:

Tried to read Gyro data
$PSTMDRSENMSG,31*<checksum>
$PSTMDRSENMSG,30*<checksum>

I even tried enabling/disabling the PSTMDRGPS message according to table CDB-ID 228 - NMEA message List 0 with the following commands:
$PSTMSETPAR,1228,800000,1 (enable message PSTMDRGPS in current config)
$PSTMSETPAR,1228,800000,2 (disable message PSTMDRGPS in current config)

=> The Teoseo VIC3DA still does not change (I have also tried enabling/disabling other messages according to table CDB-ID 228).

Only the $PSTMGETSWVER command receives a corresponding response.

Additionally, I would like to provide you with the log from the GNSS module starting from the moment the Reset was triggered at attachment.

The above procedures have been applied to many product samples in my company that use the Teoseo VIC3DA, and all produced the same results as described above.

Could you please guide me on how to receive information about the gyroscope or accelerometer? I would be very grateful to receive support from ST.

[GalaxyQuest]

Hi,

if you want to read raw accelerometer and gyroscope values, you would need to enable bit #28 in CDB-228. This will output Accel and Gyro at 100 Hz. 

$PSTMSETPAR,1228,0x10000000,1
$PSTMSAVEPAR    //save
$PSTMSRR        //reset

To handle the additional data from gyro and accel, it would be good to increase the baud rate to 460800.

$PSTMSETPAR,1102,0xC
$PSTMSAVEPAR
$PSTMSRR

You would need to SAVE and RESET for settings to take effect.

Please let me know if this is providing the information you need.

[HAO1]

Dear @GalaxyQuest 

• First of all, let me express my sincere thanks for your help.

• Previously, I also sent the command $PSTMSETPAR,1228,0x10000000,1, but since there was no save or reset command, I didn’t get the desired result. This time, I followed your three commands exactly and got the expected outcome—PSTMDRSENMSG was received at a frequency of 100 Hz. However, PSTMDRSENMSG is being exported too frequently, which is causing issues with my software buffer during processing. Could you help me set it to export at a frequency of 10 Hz instead? (I looked into UM2791, and Table CDB-ID 190 should help configure the export frequency of the messages, but there is no detailed description of how to use it.)

  

[GalaxyQuest]

Hi, 

Are you using the IMU information for dead reckoning applications or using it just for reading IMU data?

I understand you have trouble with software buffers, have you tried increasing the baud rate, so that you have data to fill up the buffer soon and not wait.

Please let me know if you have tried these approaches.

[HAO1]

Hi @GalaxyQuest 

Thank you for your answer, but it seems you have misunderstood my point. Basically, the issue I’m facing is that the number of PSTMDRSENMSG outputs per second is too high, which forces me to increase the buffer size to receive the data (my buffer also needs to accommodate other messages such as GPGGA, GPRMC, etc.). Therefore, I would like to reduce the output rate to 10 Hz to decrease the number of PSTMDRSENMSG messages per second from the GNSS UART (this output rate will also be synchronized with GPGGA, GPRMC, etc., which will make it more convenient for me to process the data when reading it into my SoC).

[GalaxyQuest · Accepted solution]

Hi,

Understood, I suggested increasing the baud rate to avoid any buffer overrun problems where the software is not reading the full message list sent if the UART is operating at a lower speed

We typically do not expose the buffer update rate because tweaking this value can interfere negatively with functioning of dead reckoning. Therefore, if you are using device for dead reckoning, I recommend you modify your software design to accept the buffer data,

If you want to change the IMU update rate, CDB-684 must be changed.

$PSTMSETPAR,1684,<imu_sampling_rate>
$PSTMSAVEPAR
$PSTMSRR

IMU_SAMPLING_RATE  is expressed in Hz.

Values from 15 to 150 Hz are accepted.
Letting the value to ‘0’ implies the usage of default fix rate, which is 100 Hz. A value lower than 15 also implies 100Hz sampling rate.

[HAO1]

Hi @GalaxyQuest 

Thank you sincerely for your help.
Your solution has been successfully applied to our hardware.
I will close this after this comment.

Have a nice day!