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Raspberry Pi Zero – Conserve power and reduce draw to 30mA

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Re: Raspberry Pi Zero – Conserve power and reduce draw to 30mA

#31

Post by noonespecial »

Andrenid wrote: post #28
janjongboom wrote: post #25

Why are we even using a Raspberry Pi for battery powered projects... 30 mA draw is so high you'll be changing batteries every 2 days, and that is without doing anything. Compare that to f.e. a normal phone chipset with deep sleep, which draws about 9 mA with a cellular connection, or .1-.2 mA in flight mode. Or, if you just use the Pi for sensor readings, get a proper microcontroller, where current is measured in mic…

For someone like me who has only just started playing with microcontrollers thanks to the Arduino and RasPi and has never touched/played with anything else.. could you give any suggestions/links on what I should consider using for sensors? I have a bunch of "nodes" I need to make, each one has a single sensor (temperature, moisture, light, or distance using a sonic sensor) that will send back to a Raspberry Pi base s…

Esp8266 wifi/micro module. You can program it in lua!

Re: Raspberry Pi Zero – Conserve power and reduce draw to 30mA

#32

Post by janjongboom »

agumonkey wrote: post #26
janjongboom wrote: post #25

Why are we even using a Raspberry Pi for battery powered projects... 30 mA draw is so high you'll be changing batteries every 2 days, and that is without doing anything. Compare that to f.e. a normal phone chipset with deep sleep, which draws about 9 mA with a cellular connection, or .1-.2 mA in flight mode. Or, if you just use the Pi for sensor readings, get a proper microcontroller, where current is measured in mic…

But are these phone chip application-class or domain specific ones ? meaning you can leverage linux ecosystem or do you have to program on their ~OS ? I was looking for the most power efficient thing that could run a minimal desktop on battery and fit into my palm.

Kinda unrelated to the whole Rpi discussion, but the SOC of any phone that runs Android would do. If that is Linux'y enough for you then it could be a solution. The problem is sourcing the SOCs. Spreadtrum makes some nice chips that include app processor, cellular, WiFi, Bluetooth, etc. for ~7$ but they're not for sale if you're not an ODM.

This is a great article [1] about how Chinese SOC manufacturers and Chinese IP works. I ended up just ripping out the mainboard of phones to get access to the SOC [2].

[1] http://www.bunniestudios.com/blog/?p=4297 [2] http://janos.io/

Re: Raspberry Pi Zero – Conserve power and reduce draw to 30mA

#33

Post by janjongboom »

Andrenid wrote: post #28
janjongboom wrote: post #25

Why are we even using a Raspberry Pi for battery powered projects... 30 mA draw is so high you'll be changing batteries every 2 days, and that is without doing anything. Compare that to f.e. a normal phone chipset with deep sleep, which draws about 9 mA with a cellular connection, or .1-.2 mA in flight mode. Or, if you just use the Pi for sensor readings, get a proper microcontroller, where current is measured in mic…

For someone like me who has only just started playing with microcontrollers thanks to the Arduino and RasPi and has never touched/played with anything else.. could you give any suggestions/links on what I should consider using for sensors? I have a bunch of "nodes" I need to make, each one has a single sensor (temperature, moisture, light, or distance using a sonic sensor) that will send back to a Raspberry Pi base s…

Depends on how they communicate between each other. I'm doing some stuff around LoRa [1] for long range communication, and my base station is a Rpi, the end nodes can be any type of microcontroller. E.g. [2] which comes with ARM's mbed, which even allows me to program them from the browser. For Bluetooth pick anything based on nrf58122, e.g. [3]. For WiFi pick ESP 8266 [4].

[1] http://www.link-labs.com/what-is-lora/ [2] http://www.multitech.com/brands/multiconnect-mdot [3] https://www.nordicsemi.com/eng/Products/Bluetooth-Smart-Blue... [4] http://www.espruino.com/ESP8266

Re: Raspberry Pi Zero – Conserve power and reduce draw to 30mA

#34

Post by petra »

Andrenid wrote: post #28
janjongboom wrote: post #25

Why are we even using a Raspberry Pi for battery powered projects... 30 mA draw is so high you'll be changing batteries every 2 days, and that is without doing anything. Compare that to f.e. a normal phone chipset with deep sleep, which draws about 9 mA with a cellular connection, or .1-.2 mA in flight mode. Or, if you just use the Pi for sensor readings, get a proper microcontroller, where current is measured in mic…

For someone like me who has only just started playing with microcontrollers thanks to the Arduino and RasPi and has never touched/played with anything else.. could you give any suggestions/links on what I should consider using for sensors? I have a bunch of "nodes" I need to make, each one has a single sensor (temperature, moisture, light, or distance using a sonic sensor) that will send back to a Raspberry Pi base s…

In general the mbed has the better options for low power , but if you prefer the arduino, this would be a good starting point:

http://jeelabs.org/tag/lowpower/

And if you want a long-range, low-power wireless connection - use LoRa , There's a driver here:

http://www.airspayce.com/mikem/arduino/RadioHead/classRH__RF...

Re: Raspberry Pi Zero – Conserve power and reduce draw to 30mA

#35

Post by jarmitage »

Andrenid wrote: post #28
janjongboom wrote: post #25

Why are we even using a Raspberry Pi for battery powered projects... 30 mA draw is so high you'll be changing batteries every 2 days, and that is without doing anything. Compare that to f.e. a normal phone chipset with deep sleep, which draws about 9 mA with a cellular connection, or .1-.2 mA in flight mode. Or, if you just use the Pi for sensor readings, get a proper microcontroller, where current is measured in mic…

For someone like me who has only just started playing with microcontrollers thanks to the Arduino and RasPi and has never touched/played with anything else.. could you give any suggestions/links on what I should consider using for sensors? I have a bunch of "nodes" I need to make, each one has a single sensor (temperature, moisture, light, or distance using a sonic sensor) that will send back to a Raspberry Pi base s…

Teensy is awesome, cheaper than Arduino and many times more powerful

http://pjrc.com/teensy/index.html

Re: Raspberry Pi Zero – Conserve power and reduce draw to 30mA

#36

Post by pjc50 »

perlin wrote: post #8

We've actually found that the RPi doesn't draw enough power, specifically to the USB ports. Our peripherals are within the USB spec of a 500ma max pull, but even so we are experiencing sporadic CPU brownouts. The first thought was to double the max_usb_current in /boot/config.txt, but that only lengthened the time between brownouts. We looked into hacks that could increase the current even more, such as this bypass m…

Splice your power supply directly across to the USB cable of the thing you're driving. For the Pi Zero, use an OTG+power cable. I think you can get cables with two A connectors (one for power, one with data+ground but no VCC) and 1 B connector.

Re: Raspberry Pi Zero – Conserve power and reduce draw to 30mA

#37

Post by agumonkey »

janjongboom wrote: post #32
agumonkey wrote: post #26

Earlier quoted context omitted.

But are these phone chip application-class or domain specific ones ? meaning you can leverage linux ecosystem or do you have to program on their ~OS ? I was looking for the most power efficient thing that could run a minimal desktop on battery and fit into my palm.

Kinda unrelated to the whole Rpi discussion, but the SOC of any phone that runs Android would do. If that is Linux'y enough for you then it could be a solution. The problem is sourcing the SOCs. Spreadtrum makes some nice chips that include app processor, cellular, WiFi, Bluetooth, etc. for ~7$ but they're not for sale if you're not an ODM. This is a great article [1] about how Chinese SOC manufacturers and Chinese I…

I thougth you were thinking of ~dumbphones, but sure enough any smartphone these days is exceptional in most features. Just today I saw a chinese dual core smartphone phone for 34$... The thing is that unless you're already in the know you can't repurpose the board.

ps: funny, just an hour ago I was trying to flash an old nexus s with CM*.

Re: Raspberry Pi Zero – Conserve power and reduce draw to 30mA

#38

Post by ZenoArrow »

noonespecial wrote: post #31
Andrenid wrote: post #28

Earlier quoted context omitted.

For someone like me who has only just started playing with microcontrollers thanks to the Arduino and RasPi and has never touched/played with anything else.. could you give any suggestions/links on what I should consider using for sensors? I have a bunch of "nodes" I need to make, each one has a single sensor (temperature, moisture, light, or distance using a sonic sensor) that will send back to a Raspberry Pi base s…

Esp8266 wifi/micro module. You can program it in lua!

Yeah, ESP8266 is a good choice for IoT projects. It supports quite a few different languages, I think the most recent addition was BASIC. It's very cheap as well (have seen people talking about prices as low as $3).

http://www.esp8266.com

Also worth knowing that the successor to the ESP8266, the ESP32, is currently in beta testing:

https://hackaday.com/2015/11/06/the-latest-best-wifi-module-...

https://twitter.com/hashtag/esp32

Re: Raspberry Pi Zero – Conserve power and reduce draw to 30mA

#39

Post by langarto »

robzyb wrote: post #24
chatman wrote: post #23

Why are you referring to the units of mA for "power", as opposed to current draw? The power consumed would be measured in watts or milliwatts.

The Raspberry Pi runs on a fixed 5 volts. At a fixed voltage power will scale linearly with current.

That's a poor excuse for not using the correct terminology or the correct units.

Re: Raspberry Pi Zero – Conserve power and reduce draw to 30mA

#40

Post by ZenoArrow »

agumonkey wrote: post #37
janjongboom wrote: post #32

Earlier quoted context omitted.

Kinda unrelated to the whole Rpi discussion, but the SOC of any phone that runs Android would do. If that is Linux'y enough for you then it could be a solution. The problem is sourcing the SOCs. Spreadtrum makes some nice chips that include app processor, cellular, WiFi, Bluetooth, etc. for ~7$ but they're not for sale if you're not an ODM. This is a great article [1] about how Chinese SOC manufacturers and Chinese I…

I thougth you were thinking of ~dumbphones, but sure enough any smartphone these days is exceptional in most features. Just today I saw a chinese dual core smartphone phone for 34$... The thing is that unless you're already in the know you can't repurpose the board. ps: funny, just an hour ago I was trying to flash an old nexus s with CM*.

> "The thing is that unless you're already in the know you can't repurpose the board."

That's why projects like Fernvale are potentially very useful, as they would make it easier to repurpose the cheap hardware used for feature phones:

https://www.youtube.com/watch?v=hpEqDPYtf9s

https://github.com/xobs/fernly

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