<story><title>Teensy 4.1 Development Board</title><url>https://www.pjrc.com/store/teensy41.html</url></story><parent_chain><item><author>ohazi</author><text>PSA: Networking on microcontrollers is a giant pain in the ass.&lt;p&gt;Don&amp;#x27;t get me wrong, boards like this (and ESP&amp;#x2F;Realtek boards with WiFi) are great for hacky prototypes. But if you&amp;#x27;re building an embedded device that will be deployed in any sort of volume, a small application processor running Linux will make your life &lt;i&gt;dramatically&lt;/i&gt; easier. You can keep it asleep most of the time if your power budget is tight.&lt;p&gt;The hard part is not cramming in an Ethernet PHY or a 2.4 GHz radio, it&amp;#x27;s the mountain of software that you need to run on top of it to get the kind of reliable, secure communications channels that we&amp;#x27;ve come to expect. Bare metal networking stacks like LwIP have a reputation for being buggy, and are nowhere near as battle-tested as the Linux&amp;#x2F;BSD networking stacks security-wise. Some of the more memory constrained devices can barely fit a complete certificate chain. Are you really prepared to roll out updates on a system like this when the next Heartbleed comes along?&lt;p&gt;Also, the layers tend to pile on, so while you might get away with a bare-bones wire protocol initially, you&amp;#x27;ll be starting your project close to the limits of what is practical. Somebody will eventually ask you if you can connect to a websocket. I know buildroot and yocto look a little scary at first, but they&amp;#x27;re better than designing yourself into a corner before you even get off the ground.</text></item></parent_chain><comment><author>freefriedrice</author><text>That&amp;#x27;s a matter of opinion.&lt;p&gt;If you don&amp;#x27;t know jack about network programming, then of course you can retreat to Linux. But Linux is not an edge &amp;#x2F; IoT platform by any stretch of the imagination. Micro RTOS is closer, but still overkill for embedded Wi-Fi.&lt;p&gt;Specifically for Wi-Fi, LWIP is -the- stack to use for embedded TCP&amp;#x2F;IP. It is under 30K with full TCP&amp;#x2F;IP and offers everything you need. Then there is COAP or MQTT, which are miniscule compared to HTTP. mbedTLS adds another 80K for full TLS compatibility on 40MHz processors. On top of this every major wifi vendor has an SDK that fits nicely into LWIP (some even ship it), some are small (CC5000) some are larger (like the WF200), but the APIs are pretty straightforward. Now, leaving TCP&amp;#x2F;IP and 802.11 will add headaches (BLE, ZigBee, Zwave) due to additional learning curves, but only because most people in embedded networking already understand TCP&amp;#x2F;IP and 802.11 phy.&lt;p&gt;If you want to play in the embedded space, you gotta learn about it. Running back to linux might work in some cases, but not constrained IoT space.&lt;p&gt;EDIT: I had my #s reversed, LWIP is under 30K, mbedTLS is around 80K, TLS is most of that (esp. RSA stuff, I could have disabled everything I didn&amp;#x27;t need [mbed has highly granular config] based on the ciphersuite and shrunk it considerably since ECC is smaller and faster than RSA). Just checked my map file, and I was in -O0 optimization mode.&lt;p&gt;EDIT2: On second thought: if people want to complain that they need linux to do networking on the edge, please complain! I&amp;#x27;ll interview after you and demonstrate MQTT with TLS v1.3 running off an MCU with a 2032 coincell for months (eh, I&amp;#x27;m weirdflexing a little, but still...)</text></comment>
<story><title>Teensy 4.1 Development Board</title><url>https://www.pjrc.com/store/teensy41.html</url></story><parent_chain><item><author>ohazi</author><text>PSA: Networking on microcontrollers is a giant pain in the ass.&lt;p&gt;Don&amp;#x27;t get me wrong, boards like this (and ESP&amp;#x2F;Realtek boards with WiFi) are great for hacky prototypes. But if you&amp;#x27;re building an embedded device that will be deployed in any sort of volume, a small application processor running Linux will make your life &lt;i&gt;dramatically&lt;/i&gt; easier. You can keep it asleep most of the time if your power budget is tight.&lt;p&gt;The hard part is not cramming in an Ethernet PHY or a 2.4 GHz radio, it&amp;#x27;s the mountain of software that you need to run on top of it to get the kind of reliable, secure communications channels that we&amp;#x27;ve come to expect. Bare metal networking stacks like LwIP have a reputation for being buggy, and are nowhere near as battle-tested as the Linux&amp;#x2F;BSD networking stacks security-wise. Some of the more memory constrained devices can barely fit a complete certificate chain. Are you really prepared to roll out updates on a system like this when the next Heartbleed comes along?&lt;p&gt;Also, the layers tend to pile on, so while you might get away with a bare-bones wire protocol initially, you&amp;#x27;ll be starting your project close to the limits of what is practical. Somebody will eventually ask you if you can connect to a websocket. I know buildroot and yocto look a little scary at first, but they&amp;#x27;re better than designing yourself into a corner before you even get off the ground.</text></item></parent_chain><comment><author>im_down_w_otp</author><text>The power budget isn&amp;#x27;t the only reason you go for an MCU. Often you&amp;#x27;re doing it for the real-time guarantees or the hardware qualification (e.g. for applications where you need something with a safety rating). That said, yes... TCP&amp;#x2F;IP based networking in the traditional embedded world isn&amp;#x27;t comparatively pleasant.</text></comment>