| DotMatrix5x7 | Drives 5x7 dot matrix display directly connected to Arduino pins |
| SingleWireSerial | Robust software serial library using a single line in half-duplex mode. |
| SoftI2CMaster | I2C lib that supports bit banging and hardware support |
| TXOnlySerial | Enables one-way serial communication (TX) on any digital pin. |
| Vcc | Measure supply voltage (using optinally stored calibration value) |