#653 – Benjamin Cabé Nose Zephyr

Welcome Benjamin Cabé of The Zephyr Project!

• Benjamin is the developer advocate at The Zephyr Project, which is both a Real Time Operating System and an ecosystem (or almost like a “distro”, rather than an OS)


• Benjamin does videos on the Zephyr YouTube and maintains an awesome blog / newsletter


• The ecosystem is deep: Chris recently learned there is a state machine framework


• Multiple people involved in dev like an OS


• The Platinmum Members includes chip companies like NXP, Nordic, ADI


• There are 600+ boards supported in the ecosystem (and more if you do custom)


• Devicetree is a tough concept, but a powerful one that was borrowed from Linux


• Who is the audience for Zephyr?


• Chromebook embedded controller


• What’s the smallest processor that Zephyr can run on? M0s can run it no problem


• Chris thinks one of the benefits is the ability to bolt new stuff on to a project


• Simulation through Wokwi (Past Guest Uri) or Renode (Past Guest Michael)


• Using different levels of abstraction


• zephyr i2c init


• Benefits of abstraction
  
  
  
  • Swapping out chips (bubblegum tapshoes)
  
  
  • Tying stuff together (bolting stuff on)
  
  
  • Infrastructure with CI/CD
  
  
  
  


• Zephyr doesn’t have an official IDE but VScode “just works”


• Helper tools from Nordic


• Open Source


• Hobby projects


• Dev survey


• Custom Keyboards (ZMK)


• RP2040 support


• Arduino recenlty joined the project


• Layers of abstraction
  
  
  
  • Architecture (ie. arm, nios2, x86)
  
  
  • SOC (available peripherals surrounding the core)
  
  
  • Board (PCB definition which might have:)
    
    
    
    • SOC
    
    
    • Memory
    
    
    • Peripherals / Sensors
    
    
    
    
  
  
  
  


• Check the tree and PRs for sensors that might be in-flight


• Compared to Arduino IDE


• Choosing ecosystems


• Weekly newsletter


• Things you didn’t know you needed: NMEA subsystem


• In Jay Carlson’s 2nd appearance on the show, he said “I’m reading more code than I’m writing”


• Benjamin’s profile photo is of his artificial nose he created a few years ago


• Making a machine model for bread (pandemic)


• It uses TFLite


• What is the project doing? (in parallel)
  
  
  
  • Acquire data
  
  
  • Machine learning inference
  
  
  • Display update
  
  
  • Network interface
  
  
  
  


• Benjamin reimplemented the Nose in Zephyr using ZBus (Chris recorded a video with the author of this subsystem)


• Like an MQTT broker on device


• Some of the concerns I (Chris) had when I was starting was not understanding RTOS concepts (threads, queues, etc). Brian Amos was on the show talking about his book, which is a great way to get started with these ideas.


• Threading / work queues


• The importance of a project when starting out


• Starter hardware
  
  
  
  • Hero devkits (Chris likes the nRF9160-DK as a starter board or the nRF5340-DK)
  
  
  • M5stack boards
  
  
  • iMX8
  
  
  
  


• Jumping down to Zephyr from Linux


• MPU + MCU


• Tight integration


• Zephyr can run POSIX code


• What about the the RT in RTOS? Does this operate realtime often? (timing critical)


• BOM cost and software cost


• Security and dependencies


• Join the Zephyr discord to talk to other people using Zephyr


• TechTalks / YouTube


• Interested in going to a conference in Seattle in 2024 for Zephyr? The ZDS / EOSS CFP is open now!