Hello guys

the M5Cardputer doesn't have that hold button until green LED lights up mechanism. To put M5Cardputer into download mode use the method described here.

If you want to enter download mode, press and hold the G0 button on StampS3 before turning it on, then release it after powering it on.

Thanks
Felix

Hello @m5stack

thank you for letting us know about the latest UIFlow 1.7.3 firmware. I appreciate it.

It is however very unfortunate that the M5Core2 PaHub bug has not been addressed in this update. I'd appreciate if your engineers fix that bug in the next update.

Or, as stated already many times in many places, please open source the UIFlow code so we can help you fix issues like that.

Thank you for listening.

Felix

Hello @jamstooks

@ajb2k3 is correct, the PbHub is for analog devices only and cannot be used for UART.

Unlike UART, I2C is a bus and can handle multiple units (as long as the units use different I2C addresses). So if you want to connect multiple I2C units to you M5Core2 you can use a Groove-T.
However as soon as some units you wish to connect share the same I2C address you need a different solution. You have two options:

• the units in question allow for the I2C address to be modified
• use a PaHub (like @ajb2k3 suggested)

As for connecting the UnitV2 to your M5Core2 via UART: I would suggest the Battery Bottom 2, which has been designed for M5Core2 and it gives you the UART port needed.

The COMMU module should work as well, but as it has been designed for the M5Stack (Basic, Gray, Go, Fire) there seems to be some incompatibility issues like while the COMMU module is stacked to the M5Core2 the M5Core2 cannot be flashed.
(Note: I don't have the COMMU module, so I cannot confirm that issue.)

Thanks
Felix

Hi guys

an M5CoreInk with ESP32 in light or deep sleep still consumes a couple of mA (which is to be expected given the hardware architecture). However M5CoreInk allows to shutdown ESP32 completely and later wake it up from the RTC timer or alarm.

For an M5CoreInk in shutdown mode I've measured a current (at the battery) of only about 2.5 uA which is pretty good. And yes, the ink display retains the last image.

Cheers
Felix

Hi guys

Here is an explanation as to why it may take some time to fix: M5CoreS3 uses the SPI bus in a special way to control the LCD: MISO (normally an input) is reconfigured to be an output and is used as DC line (instead of a dedicated GPIO for DC). Unfortunately to access the SD card (which shares the SPI bus with the LCD) MISO needs to be an input.

In case you might be interested. I found a way to do this switching back and forth between input and output for Arduino.

Thanks
Felix

Hello @Bipman

by default Port A is meant for I2C, but it can be used for I/O (Port B) or UART (Port C) as well.

Note: But please be aware, that it can be only one type of port at any given time. Also, since its default use is Port A (I2C) there are internal pull-up resistors (10 k) in place on both lines which might have a negative effect when used in a different mode.

If you need Port A and Port B at the same time there is the PbHUB unit which can be used to connect some of the Port B units.

If you need all three types of ports (A, B and C) together then I am afraid M5Cardputer is the wrong device to use as core. There are simply no more GPIOs available for a dedicated Port B and/or Port C. Please see schematic here.

Thanks
Felix

Hello guys

my M5Cardputer takes about 7 hours for a full charge from a completely discharged battery state.

Note: I soldered two LEDs to the charger IC CHRG and STDBY outputs and it switched from charging to standby after about 7 hours.

Thanks
Felix

Hello @Surya

after long hours of searching and debugging I found the reason why I2C would fail. It starts to fail as soon as SSL is invoked. The SSL library uses an analog GPIO as input for its random seed. And in your code you used GPIO2 which is one of M5AtomS3 Groove GPIOs.

So to get rid of the I2C error try changing the GPIO used for random seed to GPIO10.

//SSLClient ethClientSSL(ethClient, TAs, (size_t)TAs_NUM, 2);
SSLClient ethClientSSL(ethClient, TAs, (size_t)TAs_NUM, GPIO_NUM_10);

Thanks
Felix

Hello @koreanEggCoffee

yes, that is possible - I am powering my M5Atom this way.

However please note: There is no protection against wrong polarity so please be careful not to accidentally swapping 5 volts and GND.

I also suggest you disconnect the external 5 volts before connecting USB-C. Or in other words only connect one power source at the same time.

Please also refer to the M5Atom schematics which outlines the 5 volts connections between USB, 5v pin, Groove, LEDs and 3.3 volts regulator.

https://docs.m5stack.com/#/en/core/atom_matrix

Cheers
Felix

Hello @tomtom22

G1 and G2 are available on Port A. You are correct, G38 and G39 are not available as general IO on the M5AtomS3. They are used for I2C (and yes. the IMU is already connected to them) but additional I2C devices can be added here. M5AtomS3 documentation can be found here.

Thanks
Felix

Hello @digiajay

ok, understood.

Well, you cannot set a different EOL character and therefore you cannot use UART block read line.

However you can use block count of available and read 1 bytes etc. to read chars sent from your device. As long as the char received is not your EOL char, append them into a buffer. And when you receive your EOL char do something with the chars accumulated in the buffer, then clear the buffer and start over.

Thanks
Felix

Hello @romor001

please check out my example in the UIFlow2 Project Zone: M5Paper_Read_Intern_Temp_Humid_UIFlow2.0.9

Thanks
Felix

Hello @ioamas

thank you for reporting back. I am glad to hear you got it working.

And sorry you had to sort out a not so well assembled Battery Bottom2.

Thanks
Felix

Hello @ioamas

I'd say if you place just the Battery Bottom2 (without M5Core2 stacked) onto the Battery Bottom Charging Base and neither red or green LED light up then something's faulty.

I tested the above setup and while the battery is being charged the red LED lights up and when the battery is full the green LED is on.

If that is not the case in you setup then you could check if the pins labelled 5 V and GND on the Battery Bottom Charging Base actually deliver the 5 V from the USB-C charger. Next is checking if the pins make good contact with the Battery Bottom2.

Thanks
Felix

Hello @Marc-SKIL

unit EXT.IO2 can only control one (1) RGB LED per output. So what you get is correct. Have a look at the protocol here.

Thanks
Felix

Hello @digiajay

you can use UART x write "" block which will send data without line end and then use UART x write raw Data 0x7E to send the special line end.

Thanks
Felix

Hello @BertM

I get the same error using platform 6.4.0 which supports Arduino 2.0.11.
You can see the used platform / Arduino version in your log:

PLATFORM: Espressif 32 (6.4.0) > M5Stack StampS3
framework-arduinoespressif32 @ 3.20011.230801 (2.0.11)

Try modifying the platform parameter to:

platform = espressif32@6.9.0 ;  6.9.0 - 2.0.17

This should download platform version 6.9.0 with Arduino version 2.0.17 and with that the error is gone for me.

Thanks
Felix

Hello @laursena

unfortunately I don't know the answer to your question about the power consumption and if M5Core2 can handle it.

However what I can tell you is that you do not necessarily need the PaHubs. The M5Stack I2C weight measurement units allow for the I2C address to be modified - so you could give each unit its own I2C address and simply connect them in parallel.

Thanks
Felix

Hello @ScheduleDisplay

I am glad to hear it works for you now.

Yes, the battery will drain much faster when using ESP32 deep sleep or light sleep compared to a full shutdown.

You can find the currents for all three modes here.

Thanks
Felix

Hello @ScheduleDisplay

in order to use ESP32 deep sleep ESP32 and external power to the Grove ports need to stay on. Grove power is required for the pull-up resistors in the button unit. (Internal pull-up is too weak.)

I can get your sketch to work if I comment the following lines:

//    M5.shutdown();                    // Shutdown the display and peripherals

//    M5.disableEXTPower();             // Disable external power supply

and adding this line:

gpio_hold_dis((gpio_num_t)M5EPD_EXT_PWR_EN_PIN);

after the other gpio_hold_dis() line.

Plus adding this line:

gpio_hold_en((gpio_num_t)M5EPD_EXT_PWR_EN_PIN);

after the other gpio_hold_en() line.

Thanks
Felix