You can only connect them to SPI components like the BME280 environment sensor, RC522 RFID module, and TFT display module. The I2C/TWI pins on the Micro are on D2 and D3. For Arduino beginners ...

Quick, how do you wire up an SPI ... pin, but that’s pretty much it. Just wires, and it’ll most likely work. Now add a second device. The naïve solution found in thousands of Arduino ...

The 30-pin SIMM shown above ... to your chairs…) 16MB but due to limited amount of available IOs on the Atmega328p only 256KB can be used. Our guess it that an SPI / I2C IO extender could ...

Then, an Arduino board might be exactly what ... and Bluetooth module since they connect to different pins (the Wi-Fi shield to the SPI bus, and the Bluetooth module to the TX and RX pins).