Comments on: ESP32 CYD with LVGL: Display GPS Location, Date, and Time

By: Sara Santos

Sara Santos — Thu, 08 May 2025 09:46:54 +0000

In reply to eddy.

Hi.

You probably have a different CYD model.
Check this discussion: https://rntlab.com/question/colors-inverted-on-cyb-esp32-display/
You probably need to set the inversion on and set the RGB or BGR colors.

Regards,
Sara

By: eddy

eddy — Wed, 07 May 2025 11:52:56 +0000

Hi, the sketch loads regularly, but I have the colors inverted, and I can’t view the data. The white background is black. What could have happened?
thanks

By: Sara Santos

Sara Santos — Tue, 01 Apr 2025 09:38:50 +0000

In reply to Fabrizio Bianchi.

Hi.
Thanks for sharing your experience with those modules.
Regards,
Sara

By: Fabrizio Bianchi

Fabrizio Bianchi — Sat, 29 Mar 2025 11:29:58 +0000

Hi,
I’d like to add my experience with some modules ( 3 ) from AliExpress. The blue LED blinks only if the GPS module has begun to receive signals from the satellites, if not it stays off. The standard antenna, provided with the module, isn’t the ideal for a good reception of the signals. Testing my modules, at home, in a town with tall buildings, sometimes I got 2-3 satellites, sometimes 5-6, sometimes none at all.
In the open space, in a public park, the number of satellites was never less than 7, the blue LED was a stable ON and the speed was correctly close to zero ( my walk speed in Km/h ) while, with a few satellites, it fluctuates significantly.
One last thing, some GPS modules have a red LED instead of the blue one.

By: Sara Santos

Sara Santos — Sat, 29 Mar 2025 10:39:34 +0000

In reply to Jeff Noblet.

Hi.
Are you placing your modules outside so that they can grab good signal from satellites?
Additionally, if you live in a busy area among tall building, the signal can also be weak.

When testing the modules, did you conclude something? Are they broken or are just bad quality?

Regards,
Sara

By: Jeff Noblet

Jeff Noblet — Fri, 28 Mar 2025 19:27:52 +0000

I ordered three NEO6MV2 GPS modules from Ali Express. Only one of them seems to acquire a GPS location. One of them sends no NMEA data at all but has a blinking LED. The third sends NMEA data but can’t find any satellites and has no LED activity.

Not sure if I did something wrong or if that is typical for cheap electronics from AliExpress? I shopped for the lowest price so maybe that’s what I should have expected. I’ve had better luck with other Arduino stuff from them.

As always Rui and Sara’s tutorial and example worked great, once I found a GPS module that worked.

The uBlox “u-center” helped a lot in testing the three GPS receiver modules.

By: Francisco

Francisco — Mon, 17 Feb 2025 21:08:08 +0000

In reply to Francisco.

Always wants to leave a body of evidence. Here it is attached.
youtu.be/AoKbV20Zq6k
Thanks again.
Francisco.

By: William Q

William Q — Sat, 08 Feb 2025 02:06:56 +0000

In reply to William Q.

I figured it out (with some help from GenAI 🙂
while (millis() – start < 1000)
checks for data from the GPS and sends to the GPS+ library, but the MCU spins in that loop and doesn’t allow LVGL to update. So LVGL cannot update more than once per second, and then it has to wait for GPS+ to process and tell it about updates.
At least, this is what I think is happening.
If you change that while to check for a smaller time increment instead (I’m using 100 msecs but you could go even lower, depending on your GPS refresh/reporting rate), you get much more frequent updates from LVGL.
Incidentally, @Ben, I am using this code with a Unicore UM-982 RTK module in “moving baseline” configuration, so I’m getting accurate heading information from 2 antennas with no NTRIP correction required.

By: William Q

William Q — Sat, 08 Feb 2025 01:51:06 +0000

Thank you for another excellent tutorial! I have a strange issue with this one and I can’t figure it out. My CYD only updates every 6 or 7 seconds.
I know I’m getting updates from my GPS module at least once per second (the serial output is updating once per second), and the timer callback is 1 msec.
(Incidentally, there is a slight error in the Timer section of the blog post; the timer period is in milliseconds, not seconds, but it should still work as expected.)
Regardless of whether the antenna is moving, my display refreshes at almost exactly 6 seconds after the last update. Any ideas why?

By: Francisco

Francisco — Thu, 23 Jan 2025 17:47:53 +0000

Dear Sara;
Thanks again for sharing, and to Ben too for the SD card enhance.
The projects works fine, situated in my terrace in a 10th flat building, capturing almost 7 satellites. Good for you.
Saludos,
Francisco.