32 ms·

Can you keep RPi most of the time hibernated? Does it still draw a lot of power in sleep?

kelnos 5y ago
You don't really need to "hibernate"; shutting the entire system down and booting from scratch on each update is simpler and probably more reliable. The problem (hibernate or not) is getting the Pi to wake up, since it doesn't have a real-time clock. OP is using a RTC hat to achieve this. I do wonder what kind of power consumption it uses while sleeping.
- SavantIdiot 5y ago
  what a colossal kludge. what you're trying to accomplish is basically embedded programming 101: sleep mode + wakeup timer. RTC? pff.. even any MPU on-board oscillator with no crystal has good enough PPM and lower power than an RTC. your solution is like hunting quail with a nuke.
  - KaiserPro 5y ago
    yes, but trying to generate a nice rendered image on a stand-alone uProcessor is pretty hard. I don't like that it takes headless chrome to render, but it _works_ and fills a need for the maker. I'm pretty sure they looked at the stuff they'd need to write (A layout engine, a anti aliasing library, a calendar parsing library, an image handling library) and thought "fuck that, lets use a pi". It terms of time thats weeks full time, and even then might not be possible to fit on the uCPU of choice. just buy a realtime hat with wake up ability, for $40 max, boom job done moving to making the thing look good. Its not a product, its someone's hobby, leave them be.
    - SavantIdiot 5y ago
      > trying to generate a nice rendered image on a stand-alone uProcessor is pretty hard. Did you see the rendering? It is very simple, and does not require PIL. There are plenty of embedded GUI libraries that are specifically for this kind of application (uFX, Qt). Why not learn something new? I want HN to be a place where experts critique ideas, not a Facebook/Instagram like-fest ego-stroke. I was proposing a deeper dive to the OP so that s/he could develop better skills. I wasn't mocking OP, but I was mocking your bad idea because you didn't make anything, you just threw out a naive suggestion. Did you come here to learn or to get some karma for a dopamine hit?
      - KaiserPro 5y ago
        > I want HN to be a place where experts critique ideas I was critiquing your world view that _everyone_ must at all times go really deep into software so that everything can fit inside 4mbit of flash. I was also also critiquing your strongly held opinion that simply because a microprocessor has low power states, it doesn't mean that its quick, easy or indeed achievable to render a nice calendar entirely onboard. (it is of course possible, but I know it would take me a lot of time and be no fun.) Perhaps the goal of the project was to get something that looked nice in a time frame that was reasonable. Perhaps the goal was not to spend time learning how to do antialiasing, font handling, calendar parsing in a power constrained environment. The joy of the internet is that they have shared their work, now you can build on it and make a good looking eink calendar that's battery powered on some tiny ARM SoC with 4kb of ram. Whilst you're at it, I propose that you go out of your comfort zone and remake this https://www.secretbatcave.co.uk/projects/stock-ticker-machine/ https://www.secretbatcave.co.uk/projects/stock-ticker-machin... to make it purely electro mechanical. it can't be that hard.
colonelxc 5y ago
This very article shows how they use another product that just turns on the pi on a schedule (once a day) to render the updated calendar.
SavantIdiot 5y ago
I don't think it has a hibernate mode, but it has been a quite a hwile since I've downloaded the latest headless server build. I am currently reading 428mA at 5.0V on the power supply that is driving it. It is headless and I'm not interacting with it. (400mA w/ethernet unplugged). So that's 2W. I'm running Buster Debian build. If you got a low power command, hit me with it and I'll try it! systemctl doesn't support hibernate. I don't do any low power linux programming mainly because Cortex-A class processors (heck, even M7's) are already far outside my power budget. That is a crazy amount of power, compared to the InnoPhase T2 that draws ~300 MICRO Watts when connected and sleeping.

You don't really need to "hibernate"; shutting the entire system down and booting from scratch on each update is simpler and probably more reliable. The problem (hibernate or not) is getting the Pi to wake up, since it doesn't have a real-time clock. OP is using a RTC hat to achieve this. I do wonder what kind of power consumption it uses while sleeping.

SavantIdiot 5y ago
what a colossal kludge. what you're trying to accomplish is basically embedded programming 101: sleep mode + wakeup timer. RTC? pff.. even any MPU on-board oscillator with no crystal has good enough PPM and lower power than an RTC. your solution is like hunting quail with a nuke.
- KaiserPro 5y ago
  yes, but trying to generate a nice rendered image on a stand-alone uProcessor is pretty hard. I don't like that it takes headless chrome to render, but it _works_ and fills a need for the maker. I'm pretty sure they looked at the stuff they'd need to write (A layout engine, a anti aliasing library, a calendar parsing library, an image handling library) and thought "fuck that, lets use a pi". It terms of time thats weeks full time, and even then might not be possible to fit on the uCPU of choice. just buy a realtime hat with wake up ability, for $40 max, boom job done moving to making the thing look good. Its not a product, its someone's hobby, leave them be.
  - SavantIdiot 5y ago
    > trying to generate a nice rendered image on a stand-alone uProcessor is pretty hard. Did you see the rendering? It is very simple, and does not require PIL. There are plenty of embedded GUI libraries that are specifically for this kind of application (uFX, Qt). Why not learn something new? I want HN to be a place where experts critique ideas, not a Facebook/Instagram like-fest ego-stroke. I was proposing a deeper dive to the OP so that s/he could develop better skills. I wasn't mocking OP, but I was mocking your bad idea because you didn't make anything, you just threw out a naive suggestion. Did you come here to learn or to get some karma for a dopamine hit?
    - KaiserPro 5y ago
      > I want HN to be a place where experts critique ideas I was critiquing your world view that _everyone_ must at all times go really deep into software so that everything can fit inside 4mbit of flash. I was also also critiquing your strongly held opinion that simply because a microprocessor has low power states, it doesn't mean that its quick, easy or indeed achievable to render a nice calendar entirely onboard. (it is of course possible, but I know it would take me a lot of time and be no fun.) Perhaps the goal of the project was to get something that looked nice in a time frame that was reasonable. Perhaps the goal was not to spend time learning how to do antialiasing, font handling, calendar parsing in a power constrained environment. The joy of the internet is that they have shared their work, now you can build on it and make a good looking eink calendar that's battery powered on some tiny ARM SoC with 4kb of ram. Whilst you're at it, I propose that you go out of your comfort zone and remake this https://www.secretbatcave.co.uk/projects/stock-ticker-machine/ https://www.secretbatcave.co.uk/projects/stock-ticker-machin... to make it purely electro mechanical. it can't be that hard.

colonelxc 5y ago

This very article shows how they use another product that just turns on the pi on a schedule (once a day) to render the updated calendar.

SavantIdiot 5y ago

I don't think it has a hibernate mode, but it has been a quite a hwile since I've downloaded the latest headless server build. I am currently reading 428mA at 5.0V on the power supply that is driving it. It is headless and I'm not interacting with it. (400mA w/ethernet unplugged). So that's 2W. I'm running Buster Debian build. If you got a low power command, hit me with it and I'll try it! systemctl doesn't support hibernate. I don't do any low power linux programming mainly because Cortex-A class processors (heck, even M7's) are already far outside my power budget. That is a crazy amount of power, compared to the InnoPhase T2 that draws ~300 MICRO Watts when connected and sleeping.