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#515 – Embedded Linux with Jay Carlson
Welcome Jay Carlson!
- The new article “So you want to build an embedded Linux system” is 35,000 words. Why not a book?
- Friend of the show Drew Fustini was on embedded last week talking about building Linux
- Jason and Robert from BeagleBoard.org on TAH
- “I’m your classic electrical engineer”
- For the aforementioned article, Jay designed 10 boards with different application microprocessors.
- Took 3 hours on the software side
- Tweeted about baremetal vs linux
https://twitter.com/jaydcarlson/status/1313730320169078784
- Device tree
- Operating system
- Object files in C
- POSIX
- A33
- UBoot, Yocto, Buildroot
- Building for the A33
- Git repo
- Olinuxino A33 board
- Erik Larson on the Contextual Electronics Podcast
- Want a good exercise for learning the build system? Change where the UART is located
- What if they don’t know linux?
- “I just break stuff and cycle around and keep trying”
- Twitter thread about linux shell commands
- V3S Allwinner
- Hackaday podcast talked about the 0.8mm pitch parts
- Using higher grade parts to get more margin on (memory) parts
- $50 bucks and a weekend
- “Just try it”
- 10 breakout board with parallel board
- Adding a new driver
- NUC980 internal RAM
- Student stories
- Spotify daemon
- Networking is “free”
- SDIO wifi module for $0.60
- Set top box example
- Jay and Chris discuss a theoretical project, like a sous vide with a cap touch screen
- How big is the screen? With most of the 10 boards shown, they’d be OK up to 5″
- Newer displays have MIPI
- Most parts are older and have parallel interfaces (which can be an EMI risk)
- MP1 and A33 only have MIPI
- LVDS
- Video of the QT5 demo
- iMX8 is another category of layout
- Robert Ferenec course
- NUC
- Research lab at Univ Neb – Lincoln
- Occult tracking of pigs
- When do you switch down to a micro?
- STM32F7
- Power considerations
- $1 microcontroller article
- When should you use an RTOS?
- For most programs running on Linux, Jay recommends to wrap it in a while 1 loop.
- “Linux benefits from the whole human race”
- Combining low power and high power systems. Sometimes Jay will send data over USB (if he needs high speed transfer) or set up SPI/I2C for direct control.
- MP1 and AM335x have built in micros
- Listener questions!
- “Have any vendors contacted him to use his designs as a devkit or just permission to promote it? He mentioned working with one on GitHub for bug fixes but I think that was it.”
- Ran a verison without serpentine traces
- Overclocking the memory chip to try and break it
- Vendors should use a 0.1″ form factor
- “What CAD package did he use for all of those boards?”
- Altium
- What core elements does he try to address in the class, and as embedded systems change where does he see intro course work going?
- Intro embedded systems class
- Working on a platform to learn embedded systems
- Jay talked extensively about engineering education on Embedded.fm episode 303
- Which of the three pinmux tools (NXP, TI or ST) did Jay like the most?
- All similar
- Assume I now working hardware (an iMX6ULL series board) as a base I can work upon. After what complexity point should I consider using this embedded linux system in a project?
- Any luck interfacing with current smartphones cameras?
- Camera modules will be raw output over MIPI
- Do you see embedded linux, combined with something like etherCat or modbusTCP, as a viable replacement for PLC machines?
- This is the type of application the AM335x is targeted at
- How much did he use the dev board from each part before making its own board ?
- Not much. Most went straight to proto. THe STM32MP1 dev board stinks as a SBC.
- Hard RealTime Linux for safety applications. Why is it a good idea and why it’s a horrible idea?
- How good are different silicon vendors about upstreaming their kernel patches?
- What is upstreaming?
- Smart cameras and rear cameras example
- Quectel module with Android
- Why Lincoln, Nebraska?
- Yes Man
- Jay now works for Virtual Incision, a surgical robot company located in Lincoln.
You can find Jay via his website JayCarlson.net. You can also find him on twitter at @jaydcarlson.
Thanks to our Patrons for sponsoring today’s episode. You can become one of them by going to Patreon.com/TheAmpHour. A special thanks to our corporate sponsor Binho.