Chirp has come a long way since we first encountered the start-up, exhibiting a way to use audio bursts to transmit data between toys for children. We could see the potential for the technology in RF-constrained environments, and after an initial deal with energy supplier EDF, Chirp has made headway in the sector. Now, it has announced a new software developers’ kit (SDK) for ARM’s Cortex-M4 and Cortex-M7 microcontroller (MCU) platforms, which brings the technology to the lowest-power silicon to date. Wireless Watch’s sister service, Rethink IoT, spoke to CEO James Nesfield about the announcement, and to catch up with happenings at the firm. Nesfield said that there have been some technical optimizations with the protocol to ensure it runs…