Showing posts with label ARM. Show all posts
Showing posts with label ARM. Show all posts

Wednesday, June 17, 2020

Raspberry PI 3 Model B Rev 1.2 Power Wattage

My order of USB power meter arrived a few days ago, but only today I could put it into use by plugging it in between the power supply adapter and my RPI.

The way I test the max power consumed is by creating a small C program to do infinite loop such as:

int main()
{
   while (1) {}
}

I executed it in four separate processes (open four terminals, and run the program in each one). This way I could exhaust the whole four cores in the CPU.  I also GUI desktop on the machine (LXDE).

Here what is shown by "top":




My USB power meter shows 1.17 WH, meaning in each hour it consumes 2.37 Watt or 0.00237 KWh.  If the price per kWh charged by Utility company is 12.01 cent ($0.1201/KWH), in a day I'd pay 0.00237 KWh* $0.1201/KWh * 24 hours = $‭0.006831288‬ or about $0.0068 per day.  In a month I'd pay about $0.2 minimum.

After I killed all those four infinite loop processes, the wattage did not drop.  Instead I saw it climbed to almost 2 Watt-hour.  I think over time it probably would drop back to around 2 W (idling time).

Sunday, March 27, 2016

SBC IoT

Single Board Computer for Internet of Things now are getting more popular since Raspberry Pi.  Now we can see even 64-bit SBC with less than $40 price tag!

Following is the list of SBCs I can think of:


MakerModelCPUPriceWebsiteMisc.
Raspberry-PiRPI1 Model A+BCM2835$25https://www.raspberrypi.org
Raspberry-PiRPI1 B+$35https://www.raspberrypi.org
Raspberry-PiRPI2 Model BBCM2836$35https://www.raspberrypi.org
Raspberry-PiRPI 3 Model B$35https://www.raspberrypi.org
Raspberry-PiZero$5https://www.raspberrypi.org
CHIPAllWinner R8 (ARM)$9http://www.allwinnertech.com
Pine64Cortex-A53 AllWinner A64$15 - $29http://www.pine64.com
FriendlyARMNanoPi 2 (I/O ports compatible with RPi)Quadcore A9$24.99http://www.friendlyarm.com
Texas InstrumentsARM TIVA LaunchPADARM Cortex M4F$12.99Datasheet
STM MicroelectronicsNUCLEO-F103RBARM Cortex M3$10.33Product InfoDev. Board is compatible with Arduino


I personally like the FriendlyARM as it is more open system than Raspberry Pi. Broadcom is known for being paranoid to reveal the details of their products as we can see from their datasheets. FriendlyARM is more community-friendly and provides a lot of stuff already. With the damn-cheap price and the board is ready out of the box (unlike Rpi which still needs flash card), this kit is very exciting, even more interesting than Arduino.

Sunday, January 31, 2016

Raspberry Pi vs. Next-Big-Thing's CHIP SoC Computer


Feature
RPI 1 Model A
RPI 1 Model B
RPI 1 Model A+
RPI 1 Model B+
RPI 2ModelB
NBT CHIP

SoC
BRCM 2835
BRCM 2835
BRCM 2835
BRCM 2835

AllWinner's R8
Standard SoC Speed (MHz)
700
700
700
700
900
1000

RAM (MB)
256
512
256
512

512
Ethernet (Mbps)
N/A
100
100
100
1000
N/A

HDMI output
N/A
Yes
Yes
Yes
Yes
With extra module

Composite Video out
Yes
Yes
via 3.5 mm jack
via 3.5 mm jack
via 3.5 mm jackYes

Number of USB2.0
2
2
1
4
4
1

CPU Cores111141
StorageSD CardSD Cardmicro SDmicro SDMicroSDBuilt-in Flash
Internal Storage CapacityN/AN/AN/AN/AN/A4 MB
Camera Interface (CSI)
yesyesyesyesyes
Display Interface (DSI)
yesyesyesyesyes
Video/Graphic CoprocessorVideoCore IVVideoCore IVVideoCore IVVideoCore IVVideoCore IVPowerVR SGX544
ArchitectureARM11v6ARM11v6ARM11v6ARM11v6ARMv7ARMv7
GPIO Pins2640404040