This is the twelfth post in a series tracking the development of Tock, a safe multi-tasking operating system for microcontrollers.

Academic paper season

As many of the Tock developers gear up to submit a couple of Tock-related academic papers, our development clip has slowed a bit. This will likely last until late April, but we’ll still have weekly updates. They’ll just be a bit shorter.

Signpost

@longle2718 ported an acoustic event detection library (which he originally used for bird song detection on Android) to Tock for the Signpost audio module. It’s currently waiting on some guidance to fix build issues, but involves an FFT, some clever math and should be very cool when it’s done!

NRF51 and AES

@niklasad1 spent the week working on a driver and HIL interface for the NRF51 AES controller. The AES controller only supports ECB mode (which is insecure for streams), but he’s worked out a way to use that controller in other block cipher modes (e.g. counter mode). A conversation on IRC has some details.

TRDs (Tock Reference Documents)

We want to make Tock as accessible to read, understand and contribute to. In that spirit, we’re inheriting the practice of writing reference documents from the TinyOS community. We call them (drum roll…) Tock Reference Documents, or TRDs. Each TRD explains a specific interface in the kernel, the motivation behind its design and expected implementation details. We’ve begun to write a few as well as an overview of the TRD structure and process here.

Tock Pull Requests

Merged

• @phil-levis added support for hardware acks in the RF233 driver.

• @brghena extracted a math library from the kernel for general use

Proposed

• @daniel-scs rewrote TRD1 after some final discussions on the mailing list.