EDIT: It was quicker I though. Please test beta https://erbosoft.org/erbopubreader/ . Look to release notes. It is now implemented just from FS perspective (no UI for creating folders etc in reader fw). Bug should be also fixed.

@L4700 Hi, thank you for your feedback.
Folders - I will look at it, but I had zero time till now for this miniproject. But if I add it - there will be new beta version on erbosoft.org.
Second think is bug for sure. I had zero testers :( . But I will try to fix it and test all edge cases again.
I am still not satisfied with some slow caching operations (even when they are done once and mcu is slow) so maybe I will try to improve that too (caching of paging for different font sizes, pictures/no pictures etc.)

This was Copilot's answer.

Conclusion: Enabling I2C in UIFlow2 will cause the LED matrix of the Atom Matrix to stop working because it is internally disabled. This is due to a specification (or rather a limitation) of UIFlow2.

The LED matrix (5×5 WS2812C) of the Atom Matrix is initialized by the DisplayEnable flag of M5.begin(). In the official documentation, it is written as follows:

M5.begin(true, false, true)
SerialEnable = true
I2CEnable = false
DisplayEnable = true

In UIFlow2, when using an I2C device, I2CEnable is internally set to true, and at that time, there is a behavior where DisplayEnable is automatically turned off.

This is because the internal initialization of the M5Unified series is structured in such a way that it cannot enable I2C and the LED matrix at the same time.

I want UIFlow2 to be fixed so that I can use Matrix LED and I2C at the same time.

any news?

@scroggyg I had the same question, so I looked into it and found out it's a Molex PicoBlade 6-pin. It’s sometimes called "Micro JST", but it's really a 1.25mm pitch Molex connector.

In case anyone else comes across this post, it appears that the wires coming out of the DinMeter PortB are reversed to the label, at least on my unit. G1 is the yellow wire, and G2 is the white one. It works as expected to do a digital read on the pins for a button push.

@wwhite https://docs.m5stack.com/en/guide/realtime/openai/atomic_echo_base

@kuriko Thanks. How can I do it?

Thanks. How can I do it?

Hello @obolland

according to the schematic GNSS_TX becomes M5-RXD which is then available (depending on set dip switch) on GPIOs: 3, 13, 16, 34 or 35 which translates to pins 13, 22, 15, 26 or 2 on the M5 Stack bus.

BTW: Since you are not stacking the module you can set all dip switches to 'on' at the same time (if you like).

Note: I do not have the M5Stack GPS Module v2.1 so I cannot test this myself.

Thanks
Felix

@GiovanniCaenazzo
disconnect M5Dial
press and hold boot button at the back ofM5Dial - in the middle of Stamp Controller - it is very gentle switch
connect M5Dial to USB
M5Burner should detect com port in boot mode

@y-shibata-aqua-k

I was able to resolve this issue by updating the M5GFX library in the Arduino IDE to the latest develop branch version.
Therefore, I will close this issue.

I’ve gone back and forth on this a lot. For me, YouTube is great when I’m just trying to get a quick feel for how something works—like seeing a UIFlow block setup in action or how someone wires a sensor. It helps things “click” faster compared to reading docs alone.

But yeah, I’ve run into the same issue you mentioned—some videos skip key steps or assume you already know part of the setup. That’s where things break, especially with M5Stack since small details (like firmware version or library differences) can mess everything up.

What’s worked best for me is using videos as a starting point, then keeping the official docs and forum open alongside. Most of the time, if something doesn’t work exactly like in the video, the answer is usually buried in documentation or a forum thread.

I did follow a YouTube project once for a simple ESP32 sensor dashboard. It mostly worked, but I still had to tweak pin configs and update a library to get it running properly. So yeah—not really “copy and paste,” more like guided trial and error.

If you find a creator who explains why they’re doing something instead of just showing steps, those are worth sticking with. Otherwise, I treat videos more like demos and rely on docs/forums for the real detail.

@colintd I appreciate the follow-up, as I had been meaning to post back here as well.

Happily (for me), it's no longer getting in my way since I did ultimately decide to port my project to using STM32Cube HAL API instead of Arduino Wire APIs. After that, I've had zero such issues.

I realize that doesn't help folks much who are stuck using Arduino APIs for whatever reasons (or prefer those APIs -- there are some advantages).

Your theory is interesting, though. I honestly don't remember how deeply I looked into inter-call delays and/or deeper status checking at the time. I could believe that perhaps the Arduino Wire API implementations on different hardware could also lead to subtle timing differences... and if it is also specific to the M5 PPS device, those docs aren't ultra-specific about what the device actually expects w.r.t. delays, etc.

TL;DR: It was an interesting side quest, which I ultimately solved by changing middlewares. ╰(°▽°)╯