3 Older megaAVR® and tinyAVR® Solutions

When running one-wire communication with the USART peripheral on older tinyAVR and megaAVR devices, an external open-drain circuit is required. The USART will consume two GPIO pins for this solution. Alternatively, bit banging can be used to perform one-wire communication. This eliminates the need for external hardware and only requires one pin, at the cost of being highly CPU intensive.