Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Exploring different microcontrollers less than $1

jaycarlson.net

Post reply on HN
Print view View original

81–90 of 191 posts

Re: Exploring different microcontrollers less than $1

#81

Post by koancone »

LeifCarrotson wrote: post #80
alister wrote: post #11

If I hadn't seen this article on Hacker News today, is there any combination of plausible keywords I could have typed into Google to find this particular article if I were looking for an in-depth review of microcontrollers? I tried "best microcontrollers reviewed", "best low-cost microcontrollers", "survey of microcontrollers", and a bunch of others. Nothing that Google finds in the first 10-20 hits is as good this r…

This article is remarkable because there is typically very limited accessible blogs about topics like this. This long article requires in-depth knowledge of a large number of microcontrollers, and the time, desire, and ability to verify, collate, and summarize all that information. That's a rare combination. An ordinary journalist could not write this article. It would take hundreds or thousands of hours to gain the…

So why was it written, what is the motivation of the author?

Re: Exploring different microcontrollers less than $1

#82

Post by koancone »

drcongo wrote: post #36
alister wrote: post #11

If I hadn't seen this article on Hacker News today, is there any combination of plausible keywords I could have typed into Google to find this particular article if I were looking for an in-depth review of microcontrollers? I tried "best microcontrollers reviewed", "best low-cost microcontrollers", "survey of microcontrollers", and a bunch of others. Nothing that Google finds in the first 10-20 hits is as good this r…

I've noticed some _very_ odd things going on with Google Search results recently. The other day I tried a search for an error message from SQLAlchemy, the results were poor so I added the word `SQLAlchemy` to the query and it removed _all_ answers about databases and returned a bunch of stuff about mineral mining.

Google is increasingly returning irrelevant results in the effort to deliver the targeted content their advertisers want. I predict a future for a subscription funded search engine that just delivers lexically relevant results without all the bullshit. I for one would gladly pay to use something better than Google. The advertising monetization model is broken.

Re: Exploring different microcontrollers less than $1

#83

Post by dragontamer »

I'm not as much of an expert as the writer of this page, but this looks legit. The major $1 microcontrollers that I've worked with (Atmel series) as well as the ones that have a LOT of buzz recently (The ST STM32F0 and TI's MSP420) are all discussed and compared.

Re: Exploring different microcontrollers less than $1

#84

Post by carbocation »

StavrosK wrote: post #66
lucaspiller wrote: post #14

Earlier quoted context omitted.

Yeah if anyone is just looking to get started tinkering with embedded hardware I'd say this is the way to go. The chips were made popular by NodeMCU which uses Lua, but you can easily run Arduino or write plain C on the same hardware. I've tried a few breakout boards and my favourite is the WEMOS D1 Mini. All you need to supply is a MicroUSB cable. You can get them shipped from China for under $3: https://wiki.wemos.…

I can vouch for the D1 mini also. It's the one you want, by far. It has an on board programmer so you can power and program it from USB, while being the smallest board in size out of the popular ones. The actual smallest I've seen is one I made: https://github.com/skorokithakis/tiny-ESP8266-breakout

Have you tried the NodeMCU? (Not suggesting it, as I actually killed mine when trying to program it, but more curious about whether you’ve compared it to the Wemos D1.)

Re: Exploring different microcontrollers less than $1

#85

Post by sime2009 »

lucaspiller wrote: post #14
Yaggo wrote: post #9

Didn't read all the author's criteria, but esp8266 is worth mentioning in the context of cheap microcontrollers. https://en.wikipedia.org/wiki/ESP8266

Yeah if anyone is just looking to get started tinkering with embedded hardware I'd say this is the way to go. The chips were made popular by NodeMCU which uses Lua, but you can easily run Arduino or write plain C on the same hardware. I've tried a few breakout boards and my favourite is the WEMOS D1 Mini. All you need to supply is a MicroUSB cable. You can get them shipped from China for under $3: https://wiki.wemos.…

MicroPython runs great on the ESP8266 too.

Re: Exploring different microcontrollers less than $1

#86

Post by dragontamer »

0xbear wrote: post #21

What's really amazing is that for less than $5 nowadays you can have a 1GHz+ quad core ARM Cortex-a53 with FPU and NEON support. I mean, sure, your entire device will be more than $5, and it'll be kinda power hungry at 3W or so running full tilt, but that's a pretty beefy chip for the price of a venti Starbucks latte, capable of running full Linux, with GPU, media encode/decode, etc, etc.

> $5 nowadays you can have a 1GHz+ quad core ARM Cortex-a53 with FPU and NEON support.

And probably no realtime clock, or well-documented ADC / DAC.

Sometimes, all you gotta do is:

1. Measure a voltage from something (external temperature sensor: such as a Thermistor: a resistor whose resistance changes based on the temperature. Apply a constant current to a Thermistor, and you'll get voltage that varies with temperature)

2. Change the voltage somewhere else. (IE: ramp a motor up or down based on the temperature).

3. Do this from ~500 to 10,000 updates per second (ie: 500Hz to 10kHz / An update every 2ms to every 100 us).

Don't be fooled by CPU specs. They're actually rather unimportant in the microcontroller world. Good features to have are like... integrated OpAmps, ADCs, DACs, Timers, and other features that allow you to do job #1 and #2 better. Even an Arduino/ATMega runs at 20MHz, giving you 2000-cyles per 100-microseconds. And that's why Arduinos are so popular, because they have all the ADCs / Timers needed to do the job, and 20MHz is way faster than what most people need.

A more "premium" chip would have OpAmps, which will offer finer voltage control and more customization for the hardware engineer. I guarantee you: if you're doing hardware (aka: reading voltages and setting voltages), you will NEED a bunch of OpAmps on the board somewhere. So chips that come with integrated OpAmps can really cut down on external parts.

Most of these cheap parts go up to 100MHz (ie: 10,000 cycles per 100-microseconds), but really don't have a need to go beyond that. Besides, higher MHz means more power usage... and a lot of these uCs are designed to run on button-batteries for literally months (assuming you get the right amount of sleep). So power-efficiency severely trumps processor speed in their typical use case.

--------------------

Anyway, consider this. If you have a 1GHz chip but your ADC converter only runs at 50kHz, then you practically can't do more than 50k updates per second. Because at best, your system is only able to read the voltage level once every 50kHz.

It takes a bit of time for voltages to settle down and make a decent measurement. I'd imagine that for most of these chips and systems, they're limited by peripherals and not by CPU power.

Re: Exploring different microcontrollers less than $1

#87

Post by StavrosK »

carbocation wrote: post #84
StavrosK wrote: post #66

Earlier quoted context omitted.

I can vouch for the D1 mini also. It's the one you want, by far. It has an on board programmer so you can power and program it from USB, while being the smallest board in size out of the popular ones. The actual smallest I've seen is one I made: https://github.com/skorokithakis/tiny-ESP8266-breakout

Have you tried the NodeMCU? (Not suggesting it, as I actually killed mine when trying to program it, but more curious about whether you’ve compared it to the Wemos D1.)

Yes, many of them, and a few others. The D1 is much smaller and has no redundant pins. It's also sexier.

Re: Exploring different microcontrollers less than $1

#88

Post by ksangeelee »

alister wrote: post #11

If I hadn't seen this article on Hacker News today, is there any combination of plausible keywords I could have typed into Google to find this particular article if I were looking for an in-depth review of microcontrollers? I tried "best microcontrollers reviewed", "best low-cost microcontrollers", "survey of microcontrollers", and a bunch of others. Nothing that Google finds in the first 10-20 hits is as good this r…

It's been on my mind for a while that I could use a search engine that's seeded only with sites that contain little or no advertising or tracking.

A starting point could even be the corpus of HN articles and comments, perhaps augmented with entries from the Common Crawl archives and traditional crawling.

I tend to be interested in novel and creative work, and it seems to me that most of the sites I find most rewarding are not commercially driven.

Re: Exploring different microcontrollers less than $1

#89

Post by vidarh »

koancone wrote: post #81
LeifCarrotson wrote: post #80

Earlier quoted context omitted.

This article is remarkable because there is typically very limited accessible blogs about topics like this. This long article requires in-depth knowledge of a large number of microcontrollers, and the time, desire, and ability to verify, collate, and summarize all that information. That's a rare combination. An ordinary journalist could not write this article. It would take hundreds or thousands of hours to gain the…

So why was it written, what is the motivation of the author?

From the first sentences of this article:

> As an embedded design consultant

I know that for my own part, a lot of what I blog when I blog tends to be motivated either from increasing my professional visibility or because it's something I spend time doing anyway and where I figure I it'll be useful to someone (I know I've done it right whenever I find my own blog posts in search results a couple of years later and they answer my question)

Re: Exploring different microcontrollers less than $1

#90

Post by jjcc »

xt00 wrote: post #7

Now if somebody from China can make a list of the cheap micros under 1-2 RMB, now that would be a nice list for super low cost stuff.. that I'd be very interested in...

There's a popular CPU in China meet your requirement: http://stcmcu.com/ but in Chinese
Post reply on HN