Linux capable chip with really low power consumption?
Linux capable chip with really low power consumption?
I want to build a linux(yes i want linux specifically or a deritive of it) smartwatch as a prototype that lasts ~24 hours. Ive been looking for chips that are small and power effient enough but most of them cant run linux. If i have a 400mah battery that gives me a power budget of about 60mw... I know its possibly because there are wearos(basically android) watches that last 3-4 days. I dont know what kind of sorcery that is but that means it consumes about 15mw??? I really do feel like im miscalculating something but i checked multiple times. Do they hibernate linux/android and run it off of another chip. I also dont know how to excecute that properly and its kind of off topic of my question. So point is linux on a ~60mw budget in s smartwatch. I want to use a mip display as i really like the look and it uses little power but if ever want a heart rate sensor in it thats even more power consumpotion. Thanks in advance i guess if a saint answers this shitstorm of a question.
Have a look at this.
https://pine64eu.com/product/pinetime-smartwatch-sealed/You can see the specs and get the idea of what you might need
Yeah its a good starting point but it doesnt quite run linux. If i ever manage to get the linux part working i can just copy the rest from pinetime.
He didn't say use the smartwatch itself. He said look at the specs for what hardware you can use for your own smartwatch
- PLATFORM:
- SoC: NORDIC Semiconductor nRF52832
- CPU: 64MHz ARM Cortex-M4F
- PLATFORM:
Most of those devices do in fact sleep most of the time. It's like your phone: it may last 2-3 days standby with the screen off and nothing running but if you're running a heavy CPU/GPU load it'll chew through the battery in maybe 2-3 hours or even less pretty easily. A smart watch pretty much never runs at full power other than the maybe 5 seconds when you look at it and the display lights up and there's some animations going. Otherwise it's pretty much just polling the sensors every now and then, and going right back to sleep.
It's not hibernation or even conventional S3 where everything turns off, it's more like S2idle on modern laptops. It's still on but it does power off a lot of the peripherals and drop the clock to near nothing, but it's ready to wake up quickly on timers and interrupts, and it can handle some networking and go right back to low power within a millisecond. And similarly to PCs, those chips change speed based on demand. No point running at 800MHz if it only needs 50 MHz to read sensors every now and then and keep the Bluetooth connection alive.
Even Arduinos go from a few mA to a few μA when in sleep mode.
So basically its not possible for me with my little experience in embedded stuff and general tech savyness because its just so ridiculously well optimised and oiled? I could hack around and replicate some of it at least.
Deep sleep modes with a range of good interrupt handling is where I would start, but I don't have any specific recommendations, unfortunately.