unexpectedmaker / esp32s3 Goto Github PK

Are the 2 Stemma QT connectors using the same PINS?

I am trying to use one of them for UART and one for I2C.
Also the labels for Vertical connector is mixed up.

I'm dreaming of the PicoS3 (new invention).

It's half the size of your NanoS3, with USB-A pads on the bottom, and low-profile enough to plug directly in to a USB socket, leaving nothing more than the width of the antenna poking out, beside which is a 4-pin JST SH socket (which can be used for I²C when plugged in to a host USB device, or which can be used to power the device if it's not connected inside a USB-A socket.

It's so tiny, customers could even "hack it inside" to the plug of an existing cable, without even knowing it's inside there.

It would "expose" as many as possible other useful pins as teeny-tiny solderable points on the underside, which are covered-over with a solder mask (if we want to use them, we need to scrape off the mask first), and the very edge of the connector (below the antenna) exposes enough non-masked contact area pads that sensing a finger-touch on those exposed pins can be managed).

If there's room to cram the WS2812B behind the antenna so we can at least see its glow from inside there, that would be the icing on the minicake !

@UnexpectedMaker The S3 boards.json currently used in Platformio are not using the tinyuf2 scheme (like in ArduinoIDE).
Example: https://github.com/platformio/platform-espressif32/blob/develop/boards/um_tinys3.json
Is this intended?

It is easy possible to do as done here for an Adafruit board: https://github.com/platformio/platform-espressif32/blob/develop/boards/adafruit_feather_esp32s3_reversetft.json

Hi, I really love the s3tiny, congratulations on this great work!
However, I encountered a problem: After connecting 5V to the USB power pin on the breakout header, my board cannot be powered over the USB port anymore; D5 seems dead for whatever reason. Could you tell me which type of Z-Diode D5 exactly is? Or is there even a parts list that I did not find?
Thanks, Gerhard

Hi. I need to connect a external antenna to ProS3 . How can I do it?

All of the pins in the KiCAD schematic library for the FeatherS3 an TinyS3 are backwards. In KiCAD, the little circle is used as the attachment point, and it should be facing outward. Also, the pin labels should be internal to the part.

The ProS3 has its pins in the correct orientation

Hi! I love this board, and I'm making a smart Xylobands with a fork of WLED. I don't like the TinyS3 to be very hot while using WiFi so I turn it off after a minute because it's not needed for my project, except for the initial setup.

But right now I have a problem because the WiFi doesn't works at all, and the board overheats a lot, specially with the USB connected (using the Battery will make the board overheat but not that much). At the morning it was working correctly, but from nowhere it stopped to do.

WLED uses the AP Mode, and it doesn't shows up neither on my computer nor on my phone. I also tested a example project from Arduino-esp32 which connects to my network and it also fails (it tries to connect to my network infinitely while another ESP32 would connect almost intermediately)

What can I do? There is no error message apparently so I don't have any clue

PS: Viewing the datasheet, there is a capacitor named C5, but on my board that seems to be a resistor, which also is in short (i.e. It has continuity between its terminals). Is it normal? Or is it fried somehow? After viewing the datasheet for others type of ESP32, it seems to be normal to have a zero ohms resistor between the antenna and the ESP32

from the readme(https://github.com/UnexpectedMaker/esp32s3/tree/main/code/arduino) "example files" https://github.com/UnexpectedMaker/esp32s3/blob/main/code/arduino/examples gives a 404 error as it doesn't exist.

While doing experiments with BLE on battery power, we noticed an unexpectedly high current consumption. This makes the battery connector on the board less useful. With dynamic frequency scaling, modem-sleep and CPU pause, we got down to 25mA average. In order to get to the 2 to 5mA light-sleep mode with running BLE connections, it is necessary to connect a 32.768kHz crystal and respective load capacitors to the XTAL_32K pins.

Sadly, the XTAL_32K seem to be not connected on anything on the UM Feather S3. Maybe it could be a nice feature for future products to at least have unpopulated footprints for the crystal and capacitors on the bottom side of the board.

Using Micropython V1.19.1+, the implementation of the battery monitor on GPIO2 and get_battery_voltage() produces invalid results. The default range of the ADC with attenuation of 0dB is only 850mV (refer to the ADC Characteristics in the ESP32-S3 datasheet), so the voltage presented to the ADC from the voltage divider on GPIO2 saturates the count for any usable LiPo voltages unless some input attenuation is used.

I have obtained good results using ATTN_2_5DB and the newer ADC.read_uv() function while scaling the voltage reading using the voltage divider resistor values. For a FeatherS3 board, the code looks similar to:

# Battery voltage divider.  Voltage seen by the ADC is VBAT * R1 / (R1 + R2)
R1 = 160 # voltage divider R1 in kOhms
R2 = 442 # voltage divider R2 in kOhms

vbat_scale_factor = (R1 + R2) / R1 / 1_000_000 # to convert the microvolt reading to volts

def get_battery_voltage():
    """
    Returns the current battery voltage. If no battery is connected, returns around 4.2V which is the charge voltage
    This is an approximation only, but useful to detect if the charge state of the battery is getting low.
    """
    adc = ADC(Pin(VBAT_SENSE), atten=ADC.ATTN_2_5DB) # Assign the ADC pin to read with nominal 0..1.1V range
    # We are going to read the ADC 10 times and discard the results as we can't guarantee the ADC is calibrated or stable yet after boot. Not sure why we have to do this :(
    for _ in range(10):
        adc.read()
    measuredvbat = adc.read_uv() * vbat_scale_factor
    return round(measuredvbat, 2)

As the voltage scaling factor is derived from first principles, the values of R1 and R2 shown can be adjusted to suit other designs.

Hi,

Thank you for your boards, I love them.

I wonder if there is an error in the schematic here.

I'm not the best at electronics but isn't The P-mos T3 used for switching off the battery when connecting the USB upside down ?

Usually for a P-mos, the current is meant to flow from source to drain.

Best,

Edouard.

Is it possible to use the code for checking the amount of voltage of the battery to a much higher voltage if you make the appropriate changes in the helper file? Say I wanted to see what the voltage of a 48V battery is, would that work? Would other parts of the code need modification besides the part that sets it to 4.2v currently?

Cheers.

Some thing is missing ;)

We encountered a timing glitch with one UM FeatherS3 boards. In our hardware, we switch the system on by releasing the Feather's EN pin. Then, quite often the FeatherS3 boots into booloader mode as if the BOOT button was pressed or IO0 pulled to ground. On the oscilloscope it is visible, that the ESP32-S3 chip begins to boot, then activates the internal pullup on IO0. It seems that the voltage is up too late on IO0.

We solved this by adding a 470k resistor from IO0 to 3.3V. Now booting behaves properly.
A larger 4.7uF capacitor from RST to ground did not seem to help.

Is this a known issue? It also never appeared when combined with the Feather OLED Display.