Teensy 4.1 Development Board • Hacker News Board

Re: Teensy 4.1 Development Board

#121

Post by cactus2093 » Mon, May 11, 2020, 8:52 PM UTC

looperhacks wrote: post #106

cactus2093 wrote: post #103

Earlier quoted context omitted.

On a similar note, does anyone know of good resources for beginners for prototyping all the way through small-scale manufacturing of an embedded device? As a web & backend developer who likes to tinker with Arduino/Teensy style projects, I've always been curious what all would be involved in actually getting some units manufactured, like for a small kickstarter run or something. It seems pretty doable these days to g…

Lately I've been prototyping a small board with my goal of maybe 10 units built. For me, the process is literally putting it together on a breadboard to check if it works, then design a PCB and send it to a Chinese manufacturer. Repeat if your PCB design is faulty. (Do double check your design though, you don't want to pay for new boards and shipping every other week)

I guess one big gap for me is just the build process of how to even load code onto the device to be executed, and what type of EEPROM or flash storage or other components are required for that, once you've removed the training wheels of the plug and play dev environment.

Re: Teensy 4.1 Development Board

#122

Post by HeyLaughingBoy » Mon, May 11, 2020, 9:10 PM UTC

closeparen wrote: post #91

ohazi wrote: post #82

PSA: Networking on microcontrollers is a giant pain in the ass. Don't get me wrong, boards like this (and ESP/Realtek boards with WiFi) are great for hacky prototypes. But if you're building an embedded device that will be deployed in any sort of volume, a small application processor running Linux will make your life dramatically easier. You can keep it asleep most of the time if your power budget is tight. The hard…

>Are you really prepared to roll out updates on a system like this when the next Heartbleed comes along? Implying that embedded systems get updated...

Lots of them do. I have a bigass board right next to me with a couple dozen wires sticking out that can get updates by flash drive. We ship tons of hardware that gets updated over Ethernet or OTA.

Re: Teensy 4.1 Development Board

#123

Post by HeyLaughingBoy » Mon, May 11, 2020, 9:16 PM UTC

yjftsjthsd-h wrote: post #58

nerfhammer wrote: post #44

Earlier quoted context omitted.

Arduino you write bare metal firmware, raspPi you write software on a host OS firmware does not have the overhead of a host OS. super low power modes, instant sleep/wake, exact control of instructions/clock, far fewer security issues. Teensy and ESP32 are just souped up Arduinos.

> Teensy and ESP32 are just souped up Arduinos. Cheaper, more powerful, more feature-rich Arduinos, if you squint. I'm not sure why you would actually use an Arduino™ unless they've really improved their lineup since I last looked.

I use Arduino Nanos as modules in larger systems. I can buy them for $2.50 each, which is far less than it would cost me to build them.

Re: Teensy 4.1 Development Board

#124

Post by yjftsjthsd-h » Mon, May 11, 2020, 9:18 PM UTC

MrBuddyCasino wrote: post #118

yjftsjthsd-h wrote: post #3

Generally a very nice addition to the lineup. I'm personally fascinated by the support for soldering on an additional RAM chip; depending on how painful it is to actually access that memory, the extra 8MB could finally be enough to run uclinux.

The ESP32 can do that too. Note that PSRAM is a lot slower than the embedded SRAM, so if you need to access that memory a lot, you're going to have a bad time.

Rest assured, when I'm trying to figure out whether I can coerce Linux into running on a board that was never meant to support such a thing, "slow" is a secondary concern:)

Re: Teensy 4.1 Development Board

#125

Post by detaro » Mon, May 11, 2020, 9:18 PM UTC

fermienrico wrote: post #108

detaro wrote: post #50

Earlier quoted context omitted.

Isn't the bootloader chip the only not-open thing?

Do I get a license for hardware schematics and board layout and other aspects besides the bootloader? Where can I find a license in writing? If a license is not provided, I can't do anything with it besides hobby work. Here is the schematic page but no mention of a license: https://www.pjrc.com/teensy/schematic.html This is NOT open-source. It is visible-source. Please note, I am not demanding an open-source license.…

True, board layouts aren't either, forgot about that. The circuit itself can't be copyrighted, so you do not need a license to make your own board with the same components.

I personally quite like the approach of using the bootloader chip as light DRM: The majority of the value is in software you can freely use, with licenses provided. Prototyping with a Teensy and then making a product using the same parts and the libraries, not a problem. Just if you want to provide the same easy dev-board experience you need the bootloader chip (which you can buy and use for your own design) or invest your own development of an alternative.

Re: Teensy 4.1 Development Board

#126

Post by fermienrico » Mon, May 11, 2020, 9:24 PM UTC

detaro wrote: post #125

fermienrico wrote: post #108

Earlier quoted context omitted.

Do I get a license for hardware schematics and board layout and other aspects besides the bootloader? Where can I find a license in writing? If a license is not provided, I can't do anything with it besides hobby work. Here is the schematic page but no mention of a license: https://www.pjrc.com/teensy/schematic.html This is NOT open-source. It is visible-source. Please note, I am not demanding an open-source license.…

True, board layouts aren't either, forgot about that. The circuit itself can't be copyrighted, so you do not need a license to make your own board with the same components. I personally quite like the approach of using the bootloader chip as light DRM: The majority of the value is in software you can freely use, with licenses provided. Prototyping with a Teensy and then making a product using the same parts and the l…

Yep, I really like how the bootloader works - upgrades are drag and drop. I'll write to Paul if he is open for selling the bootloader license to me for commercial use. I am sure we can come to an agreement.

Re: Teensy 4.1 Development Board

#127

Post by jnwatson » Mon, May 11, 2020, 9:26 PM UTC

ohazi wrote: post #82

PSA: Networking on microcontrollers is a giant pain in the ass. Don't get me wrong, boards like this (and ESP/Realtek boards with WiFi) are great for hacky prototypes. But if you're building an embedded device that will be deployed in any sort of volume, a small application processor running Linux will make your life dramatically easier. You can keep it asleep most of the time if your power budget is tight. The hard…

There are several vendors of embedded RTOSs that will give you a decent TCP stack. Especially on the lower end, Linux is not a good option.

Re: Teensy 4.1 Development Board

#128

Post by jnwatson » Mon, May 11, 2020, 9:27 PM UTC

realharo wrote: post #92

adammunich wrote: post #86

Earlier quoted context omitted.

The RTOS world is much less of an 'operating system' and more so a bare-bones task scheduler. It's not like a POSIX environment at all.

Right, but doesn't it also provide some very basic level of abstraction that things like network stack implementations can target? And then many projects also come with their "standard" (not bundled, just designed for) set of basic libraries? That's the impression I'm getting from skimming through the docs. ( https://docs.zephyrproject.org/latest/guides/networking/net-... , https://www.mbed.com/en/technologies/securi…

You are correct.

Re: Teensy 4.1 Development Board

#129

Post by rwmj » Mon, May 11, 2020, 9:28 PM UTC

ohazi wrote: post #82

PSA: Networking on microcontrollers is a giant pain in the ass. Don't get me wrong, boards like this (and ESP/Realtek boards with WiFi) are great for hacky prototypes. But if you're building an embedded device that will be deployed in any sort of volume, a small application processor running Linux will make your life dramatically easier. You can keep it asleep most of the time if your power budget is tight. The hard…

It has a 32 bit processor and at least 1 MB of RAM and 8 MB of flash. This makes it considerably more powerful than the first PC I owned. Could it run Minix 3?

Re: Teensy 4.1 Development Board

#130

Post by neltnerb » Mon, May 11, 2020, 9:30 PM UTC

duskwuff wrote: post #65

jstanley wrote: post #49

Earlier quoted context omitted.

> Now that Arduino is running an ESP32 or ARM chip or has FPGA acceleration I recently used a Teensy for exactly the reasons you gave, but I'm not familiar with Arduino's with ARM or FPGA. That sounds very interesting, do you have some links where we can learn more?

Arduino has had ARM-based boards for years, starting with the Arduino Due in 2012; most of their newer boards use ATSAMD MCUs rather than the AVR8 parts they started out with. There's also a pretty active community supporting STM32 ARM hardware at https://www.stm32duino.com/ . The "FPGA acceleration", on the other hand, is pretty limited. Arduino has one board -- the MKR Vidor 4000 [1] -- with an onboard FPGA. The FP…

Thanks for the link to the Vidor, unfortunate it wasn't more functional. It'll happen someday and when it does I'll be very excited, I know that there are already hybrid FPGA/microcontroller chips as an alternative to putting a softcore microcontroller on the FPGA itself (and wasting a lot more space and speed than needed).

I await the day when I can be like "nah, pin 2 will be a 16-bit 10MHz PWM output controlled by this register and pin 7 will be a frequency counter" and then access that with code on the microcontroller as if it was a built in peripheral.

I'm kind of skeptical I'll ever really get into FPGAs otherwise, my use case for them is always so simple, at the level of... well... PWM outputs and PID loops. But a microcontroller is fast enough for most PID loops so really to me the advantage is customizable function-pin mappings. I can't imagine trying to implement something like an ethernet stack on an FPGA though, although I guess you can run DOOM on one so maybe there will be a compiler from C++ to FPGA somehow that's not comically bad. ;-)