71–80 of 90 posts
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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.
Voltage and current are easy to measure with a pair of multimeters, so it's more useful to have those numbers than wattage.
Ok, it has low power consumption... no eth, no wifi, no usb... how do you communicate and what for? Running on batteries for two days and manually coping data from sd card?
Also, there are other ways to communicate that can potentially use a lot less power than Ethernet or WiFi :)
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The MSP430 is renowned for low power and will idle (i.e. suspended waiting for interrupts) at microamps. Architecturally it's a 16 bit Von Neumann architecture at up to 16MHz with a remarkably elegant ISA and extensions to let it address more memory. Most interestingly, some devices have 64kB or 128kB of FRAM --- non-volatile RAM which operates at SRAM speeds! And because it's a Von Neumann architecture you can load…
Another argument for MSP430 as a replacement for arduino and such is that even the smallest devices support reasonable debugger. As for external devices: at least G-series need external components to generate reset pulse to reliably boot (it mostly works with reset left floating, but whether it reliably works is function of how quickly the power ramps up, I got burned by this on last project).
http://www.larsen-b.com/Article/315.html
I used it with a AVR Dragon (a rather full-featured, but still relatively inexpensive AVR programmer). You can use it with Arduino boards, of course, when you solder in the 6-pin ISP socket. (e.g. the pin header on the right of https://www.arduino.cc/en/Main/ArduinoBoardUno )
Please can somebody build a case for the Pi Zero in the form factor of the Psion 5? https://en.wikipedia.org/wiki/Psion_Series_5 (The patents on the folding keyboard will probably have expired by now -- the design dates to 1994-95 -- and with a 30mA draw the Pi 0 is within spitting distance of the sort of power the Psion 5's twin AA cells delivered. Add an e-ink display and a wee USB bluetooth peripheral for i/o (wif…
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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…
There are good answers already, here is my suggestion : once you are confortable with Arduino, look into using just the microcontroller (for example the ATMega328p of the Uno), and solder it on a protoboard with your sensors. You use the exact same code, you can easily load it via an Arduino (beware, you need an Arduino with a DIP microcontroller you can remove). Look up "Bareduino", that's the spirit. Then you can h…
The simplest programmers (ISP: In System Programmer) are only a few dollars, and they allow you to burn your creations in blank off-the-factory chips without bootloader. I think there's even an Arduino project that turns your arduino into a (very limited) STK500 compatible programmer...
[a quick web search turns up https://www.arduino.cc/en/Tutorial/ArduinoISP ]
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…
The Pi (and Arduino) is a gateway drug, imo. As a software guy, I don't think I'd have ever gotten into circuit design or hardware hacking of any sort until I brought a Pi B and Arduino Uno. For fun, first-time projects, it's a lot easier to have someone write a Python script and go, rather than breadboard a circuit and write in a more obscure, less-abstracted language.
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The Pi (and Arduino) is a gateway drug, imo. As a software guy, I don't think I'd have ever gotten into circuit design or hardware hacking of any sort until I brought a Pi B and Arduino Uno. For fun, first-time projects, it's a lot easier to have someone write a Python script and go, rather than breadboard a circuit and write in a more obscure, less-abstracted language.
check out http://wipy.io/ . Best of both worlds and draws 850uA in suspend mode.
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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…
If you need something that has clock speed in the hundreds of MHz and RAM in the hundreds of MBs then the Arietta G25 is maybe a good option - http://www.acmesystems.it/arietta . Until this current wave of boards (CHIP, RPi zero) it was pretty much on its own in the land of dev boards - substantially beefier than Arduino, ESP8266 and Teensy 3.2 but way leaner than the RPi and BBB et al. I still think it's a nice piec…
Also, is there an easy way to have an isolated realtime component, eg closed loop controller for motor drive? Could you just set up a hardware timer interrupt that preempts the kernel?
Earlier quoted context omitted.
The Pi (and Arduino) is a gateway drug, imo. As a software guy, I don't think I'd have ever gotten into circuit design or hardware hacking of any sort until I brought a Pi B and Arduino Uno. For fun, first-time projects, it's a lot easier to have someone write a Python script and go, rather than breadboard a circuit and write in a more obscure, less-abstracted language.
check out http://wipy.io/ . Best of both worlds and draws 850uA in suspend mode.