@felmue Yep, I read that wrong... my fault...

Found a little more time to troubleshoot this with the actual hardware today as well as squint at the datasheets again.

I was at least able to determine a couple more things:

I believe I've finally understood the schematics well enough to confirm that the M5 PPS operates on 3V3 I2C. I had previously gotten mixed up while trying to sort out M5's various conventions for labeling the different I2C lines (e.g. prefixes like SYS/ISO/INT/PA) as well as the fact that the M5 PPS schematic is split across two pages and I hadn't understood the precise relationship there.

TL;DR: The pins I'm using are the ISO_SCL/ISO_SCL pins as shown in the schematic below, and they are tied to the VDDB pin on the U1 isolator component, which in turn is powered via ISO_3V3 from the header.

M5 PPS I2C Pullups to 3V3 on ISO plane.png

(I also finally understand the "ISO" prefix as meaning "isolated plane", which, OK, I'll admit to a little facepalm that this wasn't obvious to me earlier.)

My wiring to the STM32 Nucleo ties ISO_SCL/ISO_SDA directly to corresponding pins on the Nucleo, while sourcing ISO_3V3 from the STM32's IOREF pin (and FWIW, I've also tried the STM32's dedicated 3V3 pin as well as probed those pins to confirm 3.3V that looks stable).

Just because it was easy to test, I tried adjusting the I2C speed parameter wayyyyy down to the comically-slow 1 kHz -- with no apparent change in behavior... but then the moment I wrote that, I realized I should check whether the Adruino TwoWire implementation I'm using actually supports arbitrary speed. Sure enough, it coerces ALL speed parameter values to one of the de facto standard values of [100 kHz, 400 kHz, 1 Mhz]. So... apparently I proved nothing via that test and doing otherwise would require hacks I'd rather not get into unless that's a pretty strong hypothesis. Sigh.

@williamsmaith just let me know. I have over 700 clients using the system with a remote dog feeding application. I even have a client using eye-tracking to send messages to feed his dog (as the feeder is mounted to his wheel chair). - cheers.

@hacxx Obviously I am missing something because UIFLOW 2.3.1 lists neither Neopixel nor Addressable LED in the unit list for me.
92997380-2da1-450c-a3aa-320539564dc8-image.png
db000a27-58a2-4945-a1ed-76af3fb29328-image.png

@hacxx I was able to work out the problem. I implemented changes to the m5stack board_m5cores3 component which makes it enable the correct AXP2101 power management for I2C for the Port A Grove port when using USB-C power.

My issue was when using the device with the DIN base and the battery on and a sensor (CO2L) plugged into the Grove Port A (I2C), the device would be working. But if I disconnect USB-C from my computer and switch off the DIN base power, then switch the DIN base back on and plug USB-C back in (simulating a complete power outage of mains and battery) the device would boot loop with the message about SDA being held low.

The only way for me to get out of the loop is to unplug the CO2L from Port A. Then the device would boot on its next attempt and the I2C port recovery would be successful. Finally, I could plugin the CO2L, reset using the button, and everything would work again.

The issue was I needed to call M5.Power.setExtOutput during setup() of the BoardM5CoreS3 class from the https://github.com/m5stack/M5CoreS3-Esphome repo's components.

void BoardM5CoreS3::setup() { M5.begin(); ESP_LOGI(TAG, "Enabling 5V power output on the external ports"); M5.Power.setExtOutput(true); ESP_LOGI(TAG, "Turning off display panel backlight"); M5.Display.setBrightness(0); }

I implemented this in a custom component which I then add as an external_component to my ESPHome config. I added additional functionality in a separate component, to expose the AXP2101 battery level, charging status, etc. I also added an automation action to allow printing out debug state info from the AXP2101, to help with debugging the IRQ and other power management concerns.

In my ESPHome config it looks like this now and the CO2L sensor works reliably now without the controller going into boot-loops from various power loss/power source change scenarios:

esphome: name: ${hostname} friendly_name: ${friendlyname} platformio_options: board_build.flash_mode: dio board_build.mcu: esp32s3 board_build.f_cpu: 240000000L libraries: - m5stack/M5Unified external_components: - source: type: git url: https://github.com/terpasaurus-midwest/esphome-fork ref: m5cores3 path: my_components refresh: 2min components: [m5cores3_power, board_m5cores3] board_m5cores3: id: m5_board m5cores3_power: id: m5_power battery_sensor: name: "Battery Level" id: battery_level battery_present_sensor: name: "Battery Present" id: battery_present battery_charging_sensor: name: "Battery Charging" id: battery_charging

@yuyun2000

Traceback (most recent call last): File "<stdin>", line 25, in <module> File "<stdin>", line 16, in setup TypeError: unexpected keyword argument 'timer_id'

@yuyun2000 said in カードピュータ1.1をラズベリーパイのbleキーボードとして使いたいのですが、ブルートゥースでペアリングができません。:

Raspberry PiのBluetooth設定Raspbian Bullseyeでは、BlueZのバージョンによってBLE互換性が異なる場合があります。以下のコマンドでBluetoothサービスを再起動し、デバイスを再スキャンしてください：
sudo systemctl restart bluetooth
bluetoothctl scan on

当初はGUIデスクトップで接続できない状態でしたが、おかげさまでCLIコマンドで bluetoothctl を使い、scan on でアドレスをスキャンし、pair <MACアドレス> で無事に接続できました。

CLIコマンドの使い方をよく知らなかったので調べるきっかけができました。ありがとうございます。

@kuriko So you are saying it is a software issue rather than hardware which seems to be the case to me. It would be really helpful to have access to the source for the unit classes so I could add functionality through inheritance.

For Core2 AWS Deep Sleep Wake:
The M5Stack Core2 AWS exposes ESP32 RTC GPIOs GPIO36 (VP), GPIO39 (VN), GPIO34, GPIO35, GPIO25, GPIO26, GPIO27, and GPIO32 for external wakeup triggers. Configure via esp_sleep_enable_ext0_wakeup() or esp_sleep_enable_ext1_wakeup(). Check the Core2 pinout to avoid conflicts with built-in peripherals.

Note: Some pins may require pull-up/down resistors. Test with low-power triggers (e.g., buttons) to verify wakeup reliability.

just load fresh firmware via M5Burner or easyloader demo version to check it out, I have Core basic which LCD stopped working few years ago after loading new project bizarre... but controller itself still works just I cant use screen

@killernils Your project is feasible with UIflow2 (MicroPython). Here's the breakdown:

Hardware Compatibility:

CoreS3 (SKU:K128) supports both Unit Weight-I2C and Module13.2 Stepmotor Driver v1.1 (SKU:M039-V11) via I2C
Stepper driver provides precise control with microstepping (FULL to 1/32 step) and step counting
Weight unit offers calibration, tare function, and filter settings through UIflow2 blocks

Required Functions Implementation:

Load Cell Calibration: Use WEIGHT_I2CUnit.set_calibration() with known weights
Tare Function: Implement via WEIGHT_I2CUnit.set_reset_offset()
Stepper Control: Utilize StepMotorDriverModule methods for direction, microstepping, and PWM frequency control
Position Tracking: Count steps using motor control commands and convert to displacement based on T8x4 rod (4mm per revolution)
Data Logging: Use UIflow2's file system blocks to save CSV data to internal storage
HMI Interface: Create buttons and plots using CoreS3's display blocks

Implementation Considerations:

Ensure proper power supply (9-24V) for the stepper driver
Implement step delay logic for smooth motor movement
Add error handling for load cell over-range conditions
Use filter functions on weight readings for stable measurements

https://chat.m5stack.com/

@GeorgeR
Have a search for 'quadcopter battery' on Amazon (or your marketplace of choice) and you should find one of the right size and correct connector. I've bought a couple of batteries and charged them with the 'Timer Power Unit' for various projects.
WARNING!! BEWARE! I've found about 50% of the batteries I've bought had the wires the opposite way round to that required by the M5Stack controllers. They will instantly kill your controller! Triple check the polarity before ever plugging them into your controller.

@jalmalogni To debug the USB keyboard issue with your Tab5 (SKU:C145/K145), please try the following steps:

Verify USB OTG Configuration: Ensure your code correctly initializes USB OTG mode. Add these build flags to your PlatformIO configuration:
build_flags =
-DARDUINO_USB_CDC_ON_BOOT=1
-DARDUINO_USB_MODE=1

Check USB Initialization Order: Modify the initialization sequence in setup():
USB.begin(); // Initialize USB first
delay(1000); // Add delay before keyboard initialization
Keyboard.begin();

Monitor USB Enumeration: Connect via WebTerminal through UiFlow2 to check if the USB device is recognized. Navigate to the serial monitor and look for USB HID initialization messages.

Test Hardware Connection: Ensure you're using the USB-C port (labeled as USB 2.0 OTG) on Tab5, not the USB-A host port. Try different USB cables known to work with data transfer.

Simplify Test Code: Use this minimal example to isolate the issue:
#include <M5Unified.h>
#include "USB.h"
#include "USBHIDKeyboard.h"

USBHIDKeyboard Keyboard;

void setup() {
M5.begin();
USB.begin();
delay(2000);
Keyboard.begin();
M5.Lcd.print("USB HID Ready");
}

void loop() {
M5.update();
if (M5.BtnA.wasPressed()) {
Keyboard.print("Hello");
Keyboard.write(KEY_RETURN);
}
}

Check Power Management: Ensure Tab5 is sufficiently powered (use external power if battery level is low). USB HID functionality may be disabled under low power conditions.

https://chat.m5stack.com/

which exact firmware are you flashing in to it?

The error means I2S port 0 driver wasn’t installed before uninstall was called. Make sure you call i2s_driver_install() successfully before attempting i2s_driver_uninstall(). Also, check that your code isn’t trying to uninstall the driver twice or uninstall before install. Reviewing the initialization sequence and adding error checks after install calls should help fix this issue. If you’re using legacy I2S, consider updating to the latest driver APIs for better stability.

Solved it, just had to scan this QR Code
https://community.m5stack.com/assets/uploads/files/1742537195503-bad5272e-aaac-47df-857b-c6d130524d36-image.png

@Handcannon Well the Core and Core2 will no longer compile in Arduino IDE with the latest board def, 3.12 and M5Stack says it is a 'me' problem and recommend I use an earlier revision.

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@smily77 Did you manage to get the SD card reader to work?