Question to Seeed: Why is the bug that analogRead (PIN_VBAT) does not work in mbed2.9.0 for XIAO_nRF52840 not resolved?

XIAO_nRF52840 has the pin to read the battery voltage, but it does not work as shown in the link below.

I submitted a post to “GitHub - Seeed-Studio/ArduinoCore-mbed” but neither 2.8.1 nor 2.9.0 solved the problem. Why doesn’t Seeed fix this bug?

Translated with DeepL

1 Like

MSFujino, thanks for finding this issue - do you know, if I’m using a firmware that itself uses PlatformIO/Arduino, where would I look to fix this error? At the moment a simple search in VisualStudio Code does not find keywords such as you changed

Hi braddo,
Sorry, I am not using PlatformIO, so I don’t know where to find the directory equivalent to “/Arduino15”.
Try to find the equivalent of the following directories and files on your PC.

C:\Users\xxxx\AppData\Local/Arduino15/packages/Seeeduino/hardware/mbed/2.9.0/cores/arduino/pinDefinitions.h : 22

Hello msfujino - I reverted to trying just Arduino. In that case, I can find the pins definition in the file pins_arduino.h Pins 14 and 31 do not existin this file. When I try to add them, I get an error during compile that those pins are invalid.

It seems like you were able to solve this in MBED, I’m hoping I can also solve it in Arduino so that I can read the battery level without an external voltage divider circuit.

I added the last two lines to try, but didn’t work:

#ifndef Pins_Arduino_h
#define Pins_Arduino_h

#include <stdint.h>

#define NUM_DIGITAL_PINS        22
#define NUM_ANALOG_INPUTS       6

#define analogInputToDigitalPin(p)  (((p)<NUM_ANALOG_INPUTS)?(analogChannelToDigitalPin(p)):-1)
#define digitalPinToInterrupt(p)    (((p)<NUM_DIGITAL_PINS)?(p):-1)
#define digitalPinHasPWM(p)         (p < EXTERNAL_NUM_INTERRUPTS)

static const uint8_t TX = 21;
static const uint8_t RX = 20;

static const uint8_t SDA = 6;
static const uint8_t SCL = 7;

static const uint8_t SS    = 20;
static const uint8_t MOSI  = 10;
static const uint8_t MISO  = 9;
static const uint8_t SCK   = 8;

static const uint8_t A0 = 2;
static const uint8_t A1 = 3;
static const uint8_t A2 = 4;
static const uint8_t A3 = 5;

static const uint8_t D0 = 2;
static const uint8_t D1 = 3;
static const uint8_t D2 = 4;
static const uint8_t D3 = 5;
static const uint8_t D4 = 6;
static const uint8_t D5 = 7;
static const uint8_t D6 = 21;
static const uint8_t D7 = 20;
static const uint8_t D8 = 8;
static const uint8_t D9 = 9;
static const uint8_t D10 = 10;

static const uint8_t D14 = 14;
static const uint8_t A31 = 31;

#endif /* Pins_Arduino_h */

Hi braddo,

What is the “Arduino” here?

Not sure if this is what your after , It did work when I tried it, Also I use Platformio and have no issues compiling or downloading or even Debugging with the jlink all works.
I do recall it using a check-mark or option for the VScode to use the same Library. but env, board, pins etc. is in the INI.
GL :slight_smile:

Arduino meaning Aduino v2 software for writing/uploading the firmware to the XIAO C3. This uses Arduino wrapper around the espressif library, not MBED (not sure what that is though). I think you mentioned in another post however that this info is only for the Sense version of XIAO.

Thanks for this - I guess it (like the thread) is somewhat specific to the Nordic based XIAO Sense. Probably some info re Platformio is also useful though - thanks for the link