ESP8266 Community Forum

- Thu Nov 17, 2016 12:49 am #58236 I am creating an autonomous Wifi environmental sensor by using BME280 and a cheap SSD1306 OLED.

So far, ESP works fine, meaning that it connects to my access point and gets an IP address from DHCP. Also the OLED works fine too.

I am running into some issues.

1. I can't find an appropriate library to make BME280 to work. I was able to do this successfully on arduinos but no luck with the ESPs. I have tried the BME280 library and the Adafruit one with no avail. Wiring is correct, it's only 2 pins SDA/SCL which connect to the GPIOs: 0,2 on the ESP module. I first thought it was the OLED which connects at the same pins but then I thought that it's i2c so it will be just fine.

2. My usb connection stops working after disconnecting and re-connecting USB on a macbook. I've read that USB power is not sufficient to power the ESP8266 and considering I've also connected an OLED, it might be the issue. Anyone that has faced the same issue ?

Thanks in advance for the replies !

- Fri Nov 18, 2016 8:46 am #58306 I have successfully used the BME280 with the ESP. Although I used a ESP-07 rather than the 01 and used the Adafruit library. I found the lack of pins on the ESP-01 also caused me issues, especially as at least GPIO0 needs to be pulled high on boot. I assume you have tested with just the BME280 attached to I2C?

I have never had success from running the ESP from USB, in fact I have had many issues with powering it and have experimented with many different batteries and regulators. On boot up it draws a lot of power which I don't think standard USB can cope with. I generally use LiPo batteries and a regulator capable of at least 200ma which work great, but you might need to add a few caps, a 100nf ceramic as close to the ESP power pins is certainly recommended.

- Fri Nov 18, 2016 3:55 pm #58343 BME280 can be jumpered for two different i2c addresses (to be compatible to bmp280).
Check default address in library, breakout boards come with both configurations.

- Tue Nov 22, 2016 9:30 am #58515 Hi,

which GPIO of ESP-07 you used to connect SSD1306 through i2c.