I have read several forums regarding the disconnecting the Arduino power from the Lithium Ion battery by itself (measuring the battery voltage and when the low limit is reached the Arduino signal turns off itself).
In my Cubieboard2 I use Lubuntu. Since I have connected barometer and arduino to my cubieboard, I read data from that devices and store it to cubieboard2 filesystem. Since NAND memory is not quite suitable for such frequent changes because of wear-out of the memory cells over time, I’ve created temp space in RAM memory. Cubieboard2 has 1GB DDR memory so there is some space for it.
I will use TMPFS and not older RAM disks – ramfs. Tmpfs is supported by the Linux kernel from version 2.4 and up. On reboot, everything in tmpfs will be lost. The memory used by tmpfs grows and shrinks to accommodate the files it contains and can be swapped out to swap space.
To get more comprehensive info regarding those filesystems read this post or this post.
I have installed lubuntu to my Cubieboard2 and I have also connected a 2.5” SATA HDD. I wanted to know if my power supply is providing enough power so I tried to measure current output from 5V power supply.
I used cheap small USB power meter (find also some on eBay for less then 5€).
My results varies according to HDD usage:
I have installed Lubuntu on my new Cubieboard 2. I have also attached HDD to SATA so I have more space to store my media. This posts describes the steps needed to install and configure media server to share my media to other devices (media players). I spent some time to select the right one and chose minidlna tool (also known as ReadyMedia, lightweight DLNA/UPnP-AV server targeted at embedded systems).
According to Ubuntu documentation the MiniDNLA daemon serves media files (music, pictures, and video) to clients on a network. Example clients include applications such as totem and xbmc, and devices such as portable media players, smartphones, and televisions.
MiniDLNA is a simple, lightweight alternative to MediaTomb, but has fewer features. It does not have a web interface for administration and must be configured by editing a text file.
The main advantage of cubieboard is it’s SATA connector. I have old HDD from notebook, so I wanted to use it as a media server.
This post has 3 parts related to HDD connected to Cubieboard2 with lubuntu:
There are many ways to see all disks and partitions but my favorite command is lsblk:
sudo lsblk -o NAME,FSTYPE,SIZE,MOUNTPOINT,LABEL NAME FSTYPE SIZE MOUNTPOINT LABEL sda 149.1G nand 3.7G |-nanda vfat 64M Volumn `-nandb ext4 3.6G / mmcblk0 241M `-mmcblk0p1 vfat 241M SSD
or also fdisk:
I’ve bought BMP085 barometric pressure sensor and my goal was to get pressure and temperature data via I2C interface to my Cubieboard running linux (cubieboard2-lubuntu-installation).
I2C bus is used by many integrated circuits and is simple to implement. Any microcontroller can communicate with I2C devices even if it has no special I2C interface so I wanted to enable I2C also in my Cubieboard2 to get direct access to sensors.
I executed the following steps to install apache with PHP on my cubieboard2 with lubuntu.
Lets start with installation that will take about 25MB:
sudo apt-get install apache2 sudo apt-get install php5 sudo /etc/init.d/apache2 restart
When I installed Lubuntu on my new Cubieboard2, the print screen was not working. When I hit the “Print Screen” button I got this message:
I’ve fixed it by installing the scrot application:
sudo apt-get install scrot
If you hit “Print Screen” or “Alt+Print Screen” you will see a new file *_scrot.png in you home directory.
When I install new Lubuntu NAND image to my new Cubieboard2 I had only 2GB of space out of 4GB available.
I followed this forum to expand the filesystem to 4GB.
sudo nand-part
In my case I used this nand-part command:
sudo nand-part -f a20 /dev/nand 32768 'bootloader 131072' 'rootfs 7569408'
the number in bootloader is the same as previous partition size.
The number in rootfs is the sum of previous partition size of partition 2 and partition 3 that we wanted to merge.