First of all, I'm a newby so there is a possibility I didn't understand some things here and there.
Alright, so for a project (a sensor hub) I bought an Wemos D1 R2 and a few sensors.
The problem is, I cannot get any of my sensors to work which use I2C. One of the I2C sensors I wanted to uses is the GY-BMP280-3.3.
So the SCL and SDA wires are both connected to the VCC line with a 10kOhm resistor.
Note that I use a non-arduino board, so the pinouts are a little different, but the D1 and D2 pins should be the correct pins according to the Wemos D1 R2 pinout:
In my wiring I used the bottom right D1 and D2.
I then used a esp8266 I2C scanner to see if I could detect the sensor, but he can't find/detect it. It keeps saying: "No I2C devices found"
So does anyone see something which could be wrong with the code, wiring, or sensor + board combination. Or has anyone some tests to maybe figure out what could be wrong?
i have a similiar circuit functioning... but without the 10k ohm resistors in between the SDA ans SCL pins... also i have the CBB pin of the sensor connected to VCC.. please try that and let me now!!
Well, after some rewiring I got the I2C scanner to pick up "a sensor" at address 0x76 (which should be BMP sensor), so that's nice. The next problem is using the sensor :
When I run the following code:
/***************************************************************************
This is a library for the BMP280 humidity, temperature & pressure sensor
Designed specifically to work with the Adafruit BMEP280 Breakout
----> http://www.adafruit.com/products/2651
These sensors use I2C or SPI to communicate, 2 or 4 pins are required
to interface.
Adafruit invests time and resources providing this open source code,
please support Adafruit andopen-source hardware by purchasing products
from Adafruit!
Written by Limor Fried & Kevin Townsend for Adafruit Industries.
BSD license, all text above must be included in any redistribution
***************************************************************************/
#include <Wire.h>
#include <SPI.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_BMP280.h>
#define BMP_SCK 13
#define BMP_MISO 12
#define BMP_MOSI 11
#define BMP_CS 10
Adafruit_BMP280 bme; // I2C
//Adafruit_BMP280 bme(BMP_CS); // hardware SPI
//Adafruit_BMP280 bme(BMP_CS, BMP_MOSI, BMP_MISO, BMP_SCK);
void setup() {
Serial.begin(9600);
Serial.println(F("BMP280 test"));
while (!bme.begin()) {
Serial.println("Could not find a valid BMP280 sensor, check wiring!");
delay(1000);
}
}
void loop() {
Serial.print("Temperature = ");
Serial.print(bme.readTemperature());
Serial.println(" *C");
Serial.print("Pressure = ");
Serial.print(bme.readPressure());
Serial.println(" Pa");
Serial.print("Approx altitude = ");
Serial.print(bme.readAltitude(1013.25)); // this should be adjusted to your local forcase
Serial.println(" m");
Serial.println();
delay(2000);
}
It says "BMP280 test. Could not find a valid BMP280 sensor, check wiring!". It could be that the code does not work on my esp8266, although I highly doubt it.
So yeah I did manage to pick it up on I2C, but still haven't been able to actually use it.
