[rektide]

lol the cortex a7 is still the go to low power arm cpu.

how a vast company with all the funding in the world can "bet on iot" but fail so miserably to make any improvement or change at all for so long is something i don't think I'll ever understand.

dont get me started on how impossible to purchase most chips are, how inaccessible/non-existant the docs are, how vendored the frak up the screwball drivers are. what a devolved old world 80's style trashfire of computing arm has been.

open source is finally building up real traction bringing light to this dark mushroom hole, Google is too exhausted & the public opinion wearing thin from unsupportable shortlived high tech devices, but what a slow slow painful march it's been dragging arm & such a broken industry into a respectable place.

[progre]

Cortex a7 is whats used on some raspberry pi boards, kind of overpowered for IoT I would think. Maybe as a hub device. Unless you go Juicero kind of cracy.

[rektide]

interesting how high this comment got then how hard it fell. +6 to +2. for my posts thats a notable swing

amusingly the critics are saying that a7 isnt the right choice, but are citing an equally aged, unmoving set of microcontrollers as what should be used. these chips at least uaually have docs, i feel like.

personally i think decent low power application processors are as much if not more of the challenge than microcontrollers to iot's developmemt. everything is a smart speaker, smart camera, has screens. watches run apps, clocks run apps. arm failing this industry miserably is quite the story. but yes, datacenters & the cloud are eattinf the world. tech is innovating ul, to bigger & bigger more expensive offerings, & the cut-throat consumer tech offerings are dying. it's a market intel bounced out of, amd commands a huge price in, and which sees nearly no wins. m3/m4+a7 forever and ever; maybe someday risc-v will shake things up.

[rurban]

The Cortex-M4 is the goto low-power CPU.

[m-ee]

Depends on your audience. M4 is decidedly midrange to me. Modern low power would probably be an M0, to others it still means 8 bit AVR.

[PennRobotics]

Normally I'd say M0+ is the king and offers good debug facilities over the M0 despite the slightly larger die size.

However, @rurban is probably correct purely because Ambiq is building their portfolio around the M4 (and M33), and they seem to be working hardest in pursuing and patenting IoT layouts/technologies that reduce energy usage.

I love AVR for teaching/learning, but the fact that you can* get a more powerful, larger memory Cortex-M at a much lower cost than, say, an Atmega... I don't know why anyone would choose AVR for a new design outside of niche uses.

(* - pre-2020)

[brandmeyer]

I love it all. Cortex-M0, M3, M4, M7, and A7 all together span several full orders of magnitude in performance. Every one of them has their niche. Unfortunately for ARM, all of those designs are many years old and they are still nearly optimal in their niches. ARMv8-M parts are starting to show up, but they aren't exactly revolutionary compared to their predecessors.

[rektide]

they're all a decade old. it's absurd that we havent found any architectural wins.

i have no idea whether there'a just scant dew wins to be had, or whether this complete lack of innovation is a company asleep at the wheel.

do you also love the cortex-a53 for application processing? because it too is another dinosaur relic that we seemingly cant eacape from. a55 seems to have made a like 12% difference.

[m-ee]

As an EE/embedded dev the M4s are approaching a mature technology for the bog standard MCU driven products I work on. You can get a 180MHz processor with 1MB of RAM and 2MB of flash. For reading sensors and doing some lightweight application layer stuff I don’t know what more I would even ask for. Current product is not power constrained so not paying much attention to that.