Feather M0 I2C

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pythonaire
 
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Feather M0 I2C

Post by pythonaire »

I running a Feather M0 RFM69 with two I2C devices (BME280 and STH31) over months. (C++ script)
Yesterday i updated the required Adafruit librarys. The board stops working, the red LED blinks.

I take my second Feather board, load the same script, nothing.
Using the adafruit I2C scanner script, nothing: no failing address, no success address.
I'm confused.

Any ideas? Thx.

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pythonaire
 
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Re: Feather M0 I2C

Post by pythonaire »

now, i tried two version of I2C scan, the Adafruit version along Adafruit_I2CDevices.h" and the basically "Wire.h" AND a naked board. The same: The scan starts, but no return (no fail, no success).
The only new thing i saw, was a update for the Adafruit board itself .

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adafruit2
 
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Re: Feather M0 I2C

Post by adafruit2 »

does blinking the onboard red led work with Blink example code? because we have been using i2c just fine for quite a while and nothing has changed with it?

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pythonaire
 
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Re: Feather M0 I2C

Post by pythonaire »

the board with red LED blinking, might have a special problem. Hover the finger over the oscillator, stops that behavior.
But the new, fresh board without any connection gave the same error.
This simple code should give an "address not found", but nothing happened.

Code: Select all

#include <Arduino.h>
#include <Adafruit_I2CDevice.h>
#include <SPI.h>

Adafruit_I2CDevice i2c_dev = Adafruit_I2CDevice(0x44);

void setup() {
  while (!Serial) { delay(10); }
  Serial.begin(115200);
  Serial.println("I2C address detection test");

  if (!i2c_dev.begin()) {
    Serial.print("Did not find device at 0x");
    Serial.println(i2c_dev.address(), HEX);
    while (1);
  }
  Serial.print("Device found on address 0x");
  Serial.println(i2c_dev.address(), HEX);
}

void loop() {
  
}

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adafruit2
 
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Re: Feather M0 I2C

Post by adafruit2 »

you need pullups on i2c

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pythonaire
 
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Re: Feather M0 I2C

Post by pythonaire »

ok, never used that before. How many ohm should i prefer? The line between the Pin and the sensor itself is around 10 cm. - Thx

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adafruit2
 
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Re: Feather M0 I2C

Post by adafruit2 »

10k

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pythonaire
 
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Re: Feather M0 I2C

Post by pythonaire »

Setting 10 k between SCL and 3V, 10 K between SDA and 3V ... nothing happened

All that since the driver/board update. For testing - do you know how i can downgrade? i use VSCode with PlatformIO extension.

Thx

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pythonaire
 
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Re: Feather M0 I2C

Post by pythonaire »

next stage ...
i dismounting an older sensor unit placed since 1 year in my garden. Check I2C (with the new board driver). All works. So, its not the driver or missing pull-up.

I bought 3 new sensors 6 months before. it seems to me, all these sensors have problems with the I2C. Test results:

- with attached I2C sensors: "Scanning ......." nothing happened
- blank, without attached I2C sensors: "Scanning ..." found I2C devices on all addresses

one of these 3 new boards might have another bug. I can't start the program upload. double press the reset button do nothing. touching the oscillator on the board (seen that here in the forum), and the upload works spontaneously.
Might all that leads to a bad production charge?

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adafruit2
 
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Re: Feather M0 I2C

Post by adafruit2 »

could be loose wiring, we use the official arduino IDE only - everyone else has no issues with this board or sensors, so i dont think its software! please follow the guides for the boards and post clear photos of the hardware

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pythonaire
 
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Re: Feather M0 I2C

Post by pythonaire »

Thx

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pythonaire
 
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Re: Feather M0 I2C

Post by pythonaire »

if you are interested ... found it.
I placed the unit outside in my gardener months and measure environmental data. the board is placed in a IP67 case, but anyway, moisture comes in the case. by deeply inspecting i see slightly copper rust at the processor along a bunch of pins. This might kill the I2C bus. I have another new fabric new board, it works well.
A mate of mine advice me to use K70 plastic coat spray to prevent moisture and corrosion.

Thx for your patience

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