IoT Zephyr

Zephyr Weekly Update – Welcoming new contributors!

Happy Friday! As you can imagine, putting this weekly digest together is rather time consuming, but luckily I am regularly improving the scripts I’m using to do the heavy-lifting of flagging noteworthy commits! This week, I added something that helps me notice who’s got their first contribution(s) merged. Therefore, it is my great pleasure to send a big shout-out to Andrew, Brandon, Jackie, Kenny, Krzysztof, Laurentiu, Patryk, Roman, Sreeram, and Theo!

New boards supported & SoC updates

  • A new variation of the NXP i.MX93 Evaluation Kit that’s specifically targeting Sound Open Firmware has been added (1b923275e6 4b27dcc88c). You can read more in the dedicated documentation page.
  • The nRF9161DK from Nordic is an upcoming single-board development kit for evaluation and development on the nRF9161 SiP for LTE-M and NB-IoT, and it’s already supported in Zephyr (4bbd91a908) 🙂
  • Initial support for the Silicon Labs EFR32BG27 BRD2602 board has been introduced (df7f10422e). This board is designed for ultra low-power scenarios (think: coin-cell powered).
  • The IT82XX2 is a 32-bit RISC-V microcontroller suitable for building embedded controllers, just like what you would find in a laptop or a smartphone. Support for the SoC as well as evaluation boards from ITE Tech, Inc. has been added this week (96df7bb833 44250a9e67). More info in the documentation too.
  • The NPM1300_EK shield is an evaluation kit for the nPM1300 Power Management Integrated Circuit (PMIC). (046dda0fa1).
    A companion sample application will help you get your ahead around the kind of functionality the PMIC provides.
    If you’re not familiar with what a PMIC is, think of it as a way to programmatically control how you want to power the different peripherals of your system. You might hook up your LCD display backlight to it, so that you can actually control its voltage based on some conditions (e.g. dim the backlight when it gets darker, or when you’re running low on battery).
  • Wi-Fi support has been added to the Espressif ESP32S3 SoC (a6c8c6e546).


Just like in previous weeks, a bunch of drivers made it into the upstream repository. I am always excited to discover new kinds of sensors–this time a color sensor 🌈–keep getting added 🙂

  • A new Bluetooth HCI driver for SiLabs BLE has been added (4a614de289).
  • Two new I2C drivers have been introduced this week:
Nordic nPM1300 PMIC
  • The nPM1300 Evaluation Kit mentioned earlier wouldn’t be incredibly useful withouth the associated driver for the actual PMIC! (d1e201ccf6)
  • The ADT7310 temperature sensor from Analog Devices is a high accuracy digital temperature sensor with up to 16-bit ((0.0078°C) resolution (b8244fdabd)
  • New driver for Würth Elektronik WSEN-PADS absolute pressure sensor (6789c0d400). Such a sensor can be useful in e.g weather stations or wearables, as you can use it to measure not only barometric pressure but also altitude.
  • And if you need a differential pressure sensor, then Würth Elektronik has you covered as they also contributed a driver for the WSEN-PDUS (73ed8ccb5f)
  • Added a new PINT driver for NXP MCUs (6f938f347b)
  • The Hamamatsu Photonics S11059 Color Sensor is an I2C digital color and Fujitsu contributed support for it this week (943158326c)
  • A new SPI driver for Renesas SmartBond™ DA1469x MCU family has been added (9cdc5d38b2)

Bluetooth Updates

New Samples

A new sample has been added for Encrypted BLE Advertising (12e9be7cc0).

Shell Output Enhancements

The Bluetooth Shell has been extended to improve the output of BLE scan data (ddf518e706).

Miscellaneous Updates

  • If you’re using Zephyr with Nordic chipsets, you’ll be interested in hearing about the added support for Nordic’s new nRF Util, which helps you program, recover, erase, etc. your device.
  • The network connectivity manager API has been updated to to generically configure and trigger post-admin-up associate/connect operations on network interfaces that support it (7c4397ae79).

As always please feel free to jump in with your thoughts or questions in the comments below. See you next week!

If you enjoyed this article, don’t forget to subscribe to this blog to be notified of upcoming publications! And of course, you can also always find me on Twitter and Mastodon.

IoT Zephyr

Zephyr Weekly Update – NVMe support, and more!

Welcome back to the Zephyr Weekly Update series, covering the week of April 8-14, 2023. It is really great to see more and more of you are starting to follow and share these updates! As always, I’ve dug through last week’s commits and GitHub activity to bring you some noteworthy highlights.

This week I’m particularly excited about the addition of NVMe controller support as it is a nice demonstration of how Zephyr can address both very small/constrained scenarios, but also bring a compelling feature set to folks looking at more advanced scenarios based on more powerful MCU/MPUs.

NVMe support

NVMe (Non-Volatile Memory Express) is a high-performance storage protocol that’s designed specifically for NAND flash memory (think: Solid-State Drives (SSD), M.2 cards, …).

NVMe logo

Thanks to several contributions from Intel, Zephyr now supports the use of NVMe controllers and disks. What’s more, the disks are being exposed through Zephyr’s standard Disk Access API, and therefore can also be used through the File System API.

If you’re used to using the Devicetree to e.g. attach an SD Card controller to an SPI bus, it will look somewhat familiar when you’ll be attaching an NVMe disk to a PCI Express interface. For example:

#include <zephyr/dt-bindings/pcie/pcie.h>
/ {
    pcie0 {
        #address-cells = <1>;
        #size-cells = <1>;
        compatible = "intel,pcie";

        nvme0: nvme0 {
            compatible = "nvme-controller";
            vendor-id = <VENDOR_ID>;
            device-id = <DEVICE_ID>;
            status = "okay";

All the commits related to adding NVMe support are linked in pull request #55643.

New boards supported & SoC updates

  • The PhyBOARD Pollux from PHYTEC is a development board featuring an i.MX 8M Plus Quad with 4×1.6 GHz cores, a neural network accelerator, and connectivity options such as Ethernet w/ TSN, RS-232, RS-485, … which make it a good option for implementing process visualization applications, quality control, etc. (e03884af and documentation page).
STM32 Nucleo-144 development board with STM32H563ZIT6 MCU
STM32 Nucleo-144 development board with STM32H563ZIT6 MCU
  • STMicroelectronics keeps working on adding support for their STM32H5 boards, this week it’s the Nucleo H563ZI (784d7321).
  • Power management support has been added for the Silicon Labs EFR32BG SoCs (c939d6a)


  • Really nice to see a new Ethernet controller driver for the popular LAN91C111 chip from SMSC/Microchip (28ff3e1d8c).
  • The TI ADS7052 is a high-speed, low-power, 14-bit ADC with 1Msps throughput (9fa35bc9a0).
  • The DS2482-800 from Analog Devices (Maxim) is a I²C to 1-Wire Bridge Device. It allows to talk to up to 8 1-Wire slaves from 1 I²C master. (691228ce01)
  • A generic NTC (Negative Temperature Coefficient) Thermistor sensor driver has been added (5d4352f).
    In order to make it more straightforward to convert raw resistance readings into actual temperature, a lookup table can be pre-generated using this script. Using the thermistor’s nominal resistance and its beta value (resistance value at 25°C / resistance value at 85°C), it spits out a lookup table in the form of a Devicetree node that the generic driver will then use to convert the measured resistance into an actual temperature.
    • You can check out the TDK RoboKit 1 board definition for an example of how the driver can be used/configured. See here for the thermistor sensor config, and here for its RT table.
  • The SmartBond DA1469x SoC from Dialog (now Renesas) is a BLE-capable Cortex-M33 based chip, and Renesas just contributed an I2C controller driver for it: (6cf3fe1d3f).
  • Support was added for the DDR memory controller on SiFive SoCs (71a6c22731)
  • The Microchip MCP970x thermistors are low-cost, low-power sensors for measuring temperature in the -40°C to +125°C range. Thanks to Nick Ward, there’s now a driver for it in Zephyr! (162c47ffc4)

Bluetooth Audio Enhancements

  • Several changes and refactoring around the Bluetooth LE Broadcast Audio functionality, in particular the implementation of the scan delegator. See PR #51679 for more details.

Noteworthy updates to existing drivers

  • The driver for the popular BMI270 IMU (Inertial Motion Unit) now supports ANY_MOTION and DATA_READY interrupts, making it possible to use the sensor in “trigger” mode vs. having to regularly poll data — quite convenient for actual motion detection, eh? (7d23e03)
  • NXP FlexCAN driver now supports CANFD variant (95b8bf3)
  • Updated Microchip MEC172x QMSPI-LDMA driver to work with Zephyr’s SPI NOR flash driver. (5c00a83)


  • The die_temp_polling samples will now work out-of-the-box for all STM32 boards (and there are dozens!), as their Devicetrees have been updated with the relevant alias (die-temp0) for exposing the CPU Die temperature sensor (fee0c82).
  • Support for Scan Delegator added to Broadcast Audio Sink sample (e00500a)
  • DHCPv4 sample now supports Arm FVP (Fixed Virtual Platform) (1ae558f5b4).
  • The new IVSHMEM Doorbell Sample Application shows how two processes on different operating systems can communicate using ivshmem (Inter-VM Shared Memory Communication).

Housekeeping / API changes

  • picolibc guru Keith Packard has proposed to change the main() return type from void to int in the entire code base. This better aligns with C and C++ standards. (see more details in PR #54628)
  • Removal of the need for a dummy device pointer in SYS_INIT functions (a5fd0d1).

As always please feel free to jump in with your thoughts or questions in the comments below, and we’ll talk next week!

Please also consider sharing the article in your professional network, as it makes a huge difference in getting these changes in front of the right people 🙂

If you enjoyed this article, don’t forget to subscribe to this blog to be notified of upcoming publications! And of course, you can also always find me on Twitter and Mastodon.

IoT Zephyr

Zephyr Weekly Update – Spring boards!

Welcome to the Zephyr Weekly Update series covering the week of March 31-April 7, 2023. By now I am hoping many of you know the drill: I look at last week’s commits and GitHub activity to extract some of the things that I think you will not want to miss!

I am really happy to see the addition of a driver for the NXP SC18IM704 (read on in the Drivers section below)—not that I care about this chip specifically, but it is demonstrating some very interesting Zephyr capabilities.

New boards supported

It’s frankly impressive to see how many new boards get added each week. See for yourself:

phyBOARD®-i.MX 8M Mini
phyBOARD®-i.MX 8M Mini
  • The phyBOARD Polis from PHYTEC is a very beefy board powered by an i.MX8MM chip (i.e. a quad-core Cortex-A53 @ 1.6 GHz + a Cortex-M4 running at 400 MHz). The carrier board is equipped with a variety of connectors and interfaces for e.g. CAN FD, WLAN, etc. (see 180f1ffb5c and documentation page).
  • The LoRa-STM32WL-DevKit from OLIMEX is a LoRa/LoRaWAN developer kit with an interesting form factor, and the ability to run out of a AA battery. (29e78deb67 added support for new revisions of the board — rev. C and rev. D).
  • Lunar Lake is Intel’s next generation of microprocessors. Support has been added upstream for the audio DSP (ADSP) that can be found in the accompanying Tensilica-powered chipset. (f5728c298d, e2881fe61a).


This week, as always, we have several new drivers joining the hundreds already available. I personally always learn a lot when skimming through those, and the first one below is a great example of what I mean by that!

  • The NXP SC18IM704 is a UART to I²C-Bus Bridge. I highly encourage you to check this driver out, even if you don’t care about this device in particular. It is a really great example of how powerful the Zephyr devicetree can be — the driver can be attached to an existing UART bus to expose nodes that effectively behave as an I2C controller (and GPIO too, since the SC18IM704 happens to have a couple). And as an application developer, you really won’t care about the “internal” UART-to-I²C ASCII-based protocol, you’ll just use the I²C API! (cd6fe580b0, 9b36e723f4).
  &uart0 {
    status = "okay";
    pinctrl-0 = <&uart0_default>;
    pinctrl-names = "default";
    sc18im704: sc18im704 {
      compatible = "nxp,sc18im704";
      status = "okay";
      target-speed = <115200>;
      reset-gpios = <&gpio1 15 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>;
      i2c_ext: sc18im704_i2c {
        compatible = "nxp,sc18im704-i2c";
        status = "okay";
        #address-cells = <1>;
        #size-cells = <0>;
      gpio_ext: sc18im704_gpio {
        compatible = "nxp,sc18im704-gpio";
        status = "okay";
        #gpio-cells = <2>;
        ngpios = <8>;
  • I am always excited to see more display drivers being added. Did I mention how much I love embedded GUIs? The Orise Tech OTM8009A LCD panel driver from Orise Tech can now be used with Zephyr (84fc689d48). You’ll find 4.63″, 800×480px, 65K colors LCD panels using this controller for just a couple of US dollars on AliExpress — hard to beat!
  • Last week a new driver for emulating UARTs. This week a new emulated RTC driver made its premiere (ae36da516a), and it can already be used on the native_posix target.
  • The SBS Gauge driver keeps getting improved to implement more features from the SBS (Smart Battery Sytem) specification. This week, support for the “AtRate” properties has been added (9727cafb41). The idea is to be able to ask the fuel-gauge IC the estimated time at which the battery may be full/empty based on a specific charge/discharge current (the rate).
  • A new rtc.h RTC (real-time clock) API header has been added to standardize communication with real-time clocks (b557a1d711). The definition of the handlers one may want to use from user space (to be notified when an alarm expires, for example) has also been added.
STMicroelectronics B-LCD40-DSI1 shield
  • MIPI-DSI host controller (as found in e.g., STM32H7 series) driver has been added (06c58fdcc2). The MIPI-DSI (Display Serial Interface) controller provides a way to interface with serial displays using a reduced number of pins.


Lastly, some interesting updates to samples:

As always please feel free to jump in with your thoughts or questions in the comments below… and see you next week! 🪁

If you enjoyed this article, don’t forget to subscribe to this blog to be notified of upcoming publications! And of course, you can also always find me on Twitter and Mastodon.