The integrated circuit sensors may come in a variety of interfaces — analogue or digital; for digital, these could be Serial Peripheral Interface, SMBus/I²C or 1-Wire. In OpenBSD, many of the I²C temperature sensors from the below list have been supported and are accessible through the generalised hardware sensors framework since OpenBSD 3.9 (2006), which has also included an ad-hoc method of automatically scanning the I²C bus by default during system boot since 2006 as well.