Problems with GPS module L76-M33

IoT Modules GNSS Module
1

Hi!
I have an L76-M33 module. In a Hardware Design says that this module supports data refresh rates up to 10 Hz. Please tell me how to increase the refresh rate to 10 Hz. 1 Hz by default is too low

2

Hi Nurruslan,

Set 10 Hz fix rate: $PMTK220,100*2F

A higher fixed rate requires a higher baud rate, so that the data can be fully output. If the fixed rate is 10 Hz (interval = 100 ms), the baud rate should be 57600 bps or higher.

Bset regards.

3

I you sure about 220 command?
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what is the differents between 300-command?

4

Hi Nurruslan,

Yes. According to Quectel_Lx0&Lx6&LC86L&LG77L_GNSS_Protocol_Specification_V2.1.pdf , $PMTK220 command is to set position fix interval.

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5

Thank you for your answers!
Now I have one main problem.
I set boud to 115200 ($PMTK251,1152001F\r\n)
And 10Hz update rate ($PMTK220,1002F\r\n)
The module send messages 10 times per second. It works fine. All messages is correct.
But, the speed measurement delay is too long. About 1.5 seconds. I mean that I start abruptly from 0 km/h in the car and only after 1.5-2 seconds the speed gets above 0. When I accelerate to 40 km/h, the module first shows 25 and after 2 seconds it reaches 40 km/h

Number of satellites 12-17.
What settings should I change so that the speed value updates faster without delay?

Maybe leave only the GPS? Or leave only RMC packages?

6

Hi Nurruslan,

Maybe leave only RMC or VTG would help.

Best regards.

7

Hello,

I take the chance of this existing topic to ask another question.
I am testing L76-M33 module and I am using following settings: baud rate 38400 and refresh rate 5Hz.

I am experiencing the following behavior for the L76-M33 module.

I get zero speed from the GPS if the speed is less than about 1.5km/h.

I am comparing L76 module with another GPS module which is able to return a speed different from zero in the same conditions.

Is there any setting that I can change to get the speed different from zero even for speed less than 1.5km/h?
For my application I need the speed to be different from zero even if moving slower than 1.5km/h.

Thanks in advance

Best regards

Giulio

8

Hi Giulio Iselqui,

If your product usually work in low speed condition, you can switch to Fitness Mode. Also, please set static navigation threshold to 0 m/s. Static navigation threshold aims to mute very low speed which will cause statical drift.

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Best regards.