23 ms·

I'm genuinely curious how popular µCs with 256 bytes of RAM actually are - the marketing for stuff like the Arduino and the whole IoT thing, while an annoying m

by i336_ 10y ago

I'm genuinely curious how popular µCs with 256 bytes of RAM actually are - the marketing for stuff like the Arduino and the whole IoT thing, while an annoying mosquito, is very effective at suggesting that the <1K scale is all but forgotten. How much of a deployed base - and perhaps more importantly, how much future demand - is out there for this sort of thing? Would it be worth it for me (as a random person on the Internet, not OP) to spend the next N years learning these microcontrollers' instruction sets, errata and idiosyncrasies? Like OP, I'm incredibly interested in assembly language, and "really tiny microcontrollers!" is one of the instinctive responses I also gave in my own answer, but I'm not sure how widespread demand for it is, so I was somewhat more cautious.

sokoloff 10y ago
These µCs are Harvard architecture (contrast Von Neumann of typical computers), with the program being stored in ROM (typically Flash) and the RAM being only for variables. The program size, therefore, is not confined to 256 bytes. They are absolutely here to stay in consumer products. Whether the job market will be good and constant over the next 25 years is something that I can't say, but they're likely not going away, and to the extent they do, they'll likely be replaced with something so similar that those skilled in the art will still be able to adapt.
- i336_ 10y ago
  Ah, I see. I wonder if compilation for Harvard architectures is any more or less difficult than for Von Neumann. I'm guessing there are pros and cons with both. Thanks for mentioning that they're here for a good bit yet, I'll definitely take a look at them.
smoyer 10y ago
Take a look at the Microchip [1] PIC series microcontrollers. With a chip and a few parts on a breadboard you can essentially make your own version of an Arduino with a much smaller footprint. I mostly do enterprise software now (at work) but I had a consulting project recently to send a PIC-based sensor and control system down an oil well. Try sending an Arduino or Rasberry Pi into a high-temperature, high-pressure environment. These parts are sold by a lot of vendors but you can get everything you need from Digikey [2]. And when you're trying to build a consumer device, it's nice to buy a microcontroller that is inexpensive - you can get this [3] one for $0.38 if you buy 3000 at a time. We normally started with flash parts and committed to OTP once our firmware was solid. [1] http://www.microchip.com/ http://www.microchip.com/ [2] http://www.digikey.com/product-search/en?keywords=microchip http://www.digikey.com/product-search/en?keywords=microchip [3] http://www.digikey.com/product-detail/en/microchip-technology/PIC10F202T-I-OT/PIC10F202T-I-OTTR-ND/665884 http://www.digikey.com/product-detail/en/microchip-technolog...
- i336_ 10y ago
  I understand that the Arduino is mostly a brand associated with the education and rapid hobbyist prototyping sectors, and that it's just eg an ATMEGA328 with a custom bootloader to make bricking the chip really really hard. I didn't think about environmental restrictions though, that's really interesting to take into account, huh. Looks like the single-unit (or handful-of-units) price is $1.14 for the PIC10F202T, which is very nice considering that Digikey is in a bit of a different class to the Chinese OEM Arduino clones you'll find on eBay for $2-$3. I am curious though - I remember reading in one of my old phonebook-sized product catalogs that certain variants of the PIC line were not recommended for new designs. Does the PIC10F202T fit into that category? I can't see any indication for or against on the webpage, nor any links that look like they'd reveal that info. (I ask because my memory of exactly what was marked legacy is poor, and I remember that some of the PIC10 range was listed as such, but I don't recall exactly which. I'm also curious what this marking means exactly - whether the chip will be phased out at some point, or what.)

by i336_ 10y ago

sokoloff 10y ago

These µCs are Harvard architecture (contrast Von Neumann of typical computers), with the program being stored in ROM (typically Flash) and the RAM being only for variables. The program size, therefore, is not confined to 256 bytes. They are absolutely here to stay in consumer products. Whether the job market will be good and constant over the next 25 years is something that I can't say, but they're likely not going away, and to the extent they do, they'll likely be replaced with something so similar that those skilled in the art will still be able to adapt.

i336_ 10y ago
Ah, I see. I wonder if compilation for Harvard architectures is any more or less difficult than for Von Neumann. I'm guessing there are pros and cons with both. Thanks for mentioning that they're here for a good bit yet, I'll definitely take a look at them.

smoyer 10y ago

Take a look at the Microchip [1] PIC series microcontrollers. With a chip and a few parts on a breadboard you can essentially make your own version of an Arduino with a much smaller footprint. I mostly do enterprise software now (at work) but I had a consulting project recently to send a PIC-based sensor and control system down an oil well. Try sending an Arduino or Rasberry Pi into a high-temperature, high-pressure environment. These parts are sold by a lot of vendors but you can get everything you need from Digikey [2]. And when you're trying to build a consumer device, it's nice to buy a microcontroller that is inexpensive - you can get this [3] one for $0.38 if you buy 3000 at a time. We normally started with flash parts and committed to OTP once our firmware was solid. [1] http://www.microchip.com/ http://www.microchip.com/ [2] http://www.digikey.com/product-search/en?keywords=microchip http://www.digikey.com/product-search/en?keywords=microchip [3] http://www.digikey.com/product-detail/en/microchip-technology/PIC10F202T-I-OT/PIC10F202T-I-OTTR-ND/665884 http://www.digikey.com/product-detail/en/microchip-technolog...

i336_ 10y ago
I understand that the Arduino is mostly a brand associated with the education and rapid hobbyist prototyping sectors, and that it's just eg an ATMEGA328 with a custom bootloader to make bricking the chip really really hard. I didn't think about environmental restrictions though, that's really interesting to take into account, huh. Looks like the single-unit (or handful-of-units) price is $1.14 for the PIC10F202T, which is very nice considering that Digikey is in a bit of a different class to the Chinese OEM Arduino clones you'll find on eBay for $2-$3. I am curious though - I remember reading in one of my old phonebook-sized product catalogs that certain variants of the PIC line were not recommended for new designs. Does the PIC10F202T fit into that category? I can't see any indication for or against on the webpage, nor any links that look like they'd reveal that info. (I ask because my memory of exactly what was marked legacy is poor, and I remember that some of the PIC10 range was listed as such, but I don't recall exactly which. I'm also curious what this marking means exactly - whether the chip will be phased out at some point, or what.)