Chirp has come a long way since we first encountered the startup, exhibiting a way to use audio bursts to transmit data between toys for kids. We could see the potential for the technology in RF-constrained environments, such as Chirp’s win with EDF’ and in the years since, Chirp has made headway in the sector. Now, it has announced a new SDK for Arm’s Cortex-M4 and Cortex-M7 microcontroller platform, which brings the technology to the lowest-power silicon to date. We 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 on the lower-power chips, and that R&D…