Recently I have been prototyping with ESP8266 (ESP-12E), Bosch BME280 temperature/pressure/humidity sensor and tiny 128×64 SSD1306 OLED display.

Sensor and display are both connected to ESP12E’s HSPI-port and from software perspective I have used Espressif’s non-OS SDK 2.0.0 and Richard A. Burton’s rboot as a basis for my firmware.