Turn-key PCB assembly services in prototype quantities or low-volume to mid-volume production runs

Using Raspberry Pi sftp server

There are several ways of accessing Raspberry Pi files through the network. One of the preferred methods is to use the Secure Copy (SCP). It is a file sending command allowing transferring data over SSH. This is a secure way of sending files between Raspberry Pi boards or other Linux machines. To use with Windows, you need special software like WinSCP. As you can see, it requires additional software to access files from windows. But if you are used transferring data via FTP, then you have another option – SFTP which is an FTP with encryption. SFTP is already enabled in Raspbian and can be used right away. Be sure that your FPT client supports sftp protocol. For instance, FileZilla, Bitvise and same WinSCP clients work without a problem. To connect to Raspberry Pi via sftp you need to enter an IP address and port 22. Log in by using your connection credentials that are pi/raspberry by default. Once connected you can drag and drop your files in and out. If you want to move a bit forward and be… Continue reading

Internet connected power usage monitor

Our homes are filling with energy hungry devices. Some of them are constantly active like fridge, routers, lighting, some switched off or on stand-by. Each of them takes some portion of energy that reflects on the end month bill. Some things you can control, but some not. So in order to hunt inefficient nodes you need some sort of energy usage monitoring. You can find lots of implementations where some are simple indicators, other are advanced and web enabled. TSalwach @ github.com have built his own version of energy monitoring system which looks really promising. His implementation monitors all three phases where he extracts several parameters: RMS Voltages and currents on each phase Apparent power (product of RMS voltage and RMS current) Real (active) power Reactive power with inductance/capacitance indication (time delay method *) Power factor Frequency (zero crossing detection with linear interpolation) Energy Tariff indication Costs of energy and alternative cost (on single tariff) He used two microcontroller boards to for this task. First one is Raspberry Pi which takes care of web accessibility, data storage and interpretation. The… Continue reading

Python web server in Raspberry Pi

There are many ways of serving web pages from Raspberry Pi. One of the ways is to install Apache webserver software. This is still a standard solution for most of the purposes. These things require quite some performance, and this is not always an optimal choice. If you need a simple web server for your home project that would efficiently work with GPIO you could try a Python web server. Are you interested to learn the most trending programming language ‘Python’? Then Intellipaat ‘Python Online Training‘ is for you. Python web server relies on flask – an extension that provides web microframework. It allows building and rendering webpages with few lines of code. Sankar has written a short tutorial on how to start with a simple static webpage from Raspberry Pi. From there you can move on with more advanced pages that include dynamic content and so on. Continue reading

Tearing Raspberry Pi Zero apart

Raspberry Pi Zero is really minimalist but yet powerful minicomputer featuring all necessary parts required to run Linux or other operating system. It features Broadcom BCM2835 processor at 1GHz, 512MB of DDR2 RAM, micro-SD slot, mini-HDMI capable to output 1080p60 video, micro USB for data and power, 40-pin GPIO, unpopulated composite video. All this fits in to 65mm x 30mm x 5mm form factor. Price for it is ridiculously low – $5. you may need micro-USB to USB adapter and HUB if you would like to have WiFi functionality, or connect keyboard. It is ideal small embedded Linux based board that is more power efficient than standard Raspberry Pi boards and still can run powerful control applications. Lets leave this topic to other debates. electroupdate shared his video where he tears one Raspberry Pi Zero apart. Simply speaking there is nothing much to tear. But probably most interesting part is processor and memory sandwiching called package on package (POP). This great solution to squeeze several chips in to small space. In other hand this practically takes out any chances to… Continue reading

Compact Raspberry Pi camera

There are several Raspberry Pi based camera projects. PiJuice decided to build something even smaller, so he came up with compact camera project. He’s chosen Raspberry Pi A+ which is smallest Rasberry Pi. Next thing he had to deal with was power supply. He used PiJuice module which takes care of charging battery and generating necessary voltage for Raspberry Pi. There is one obvious choice for camera module so nothing to add here. On a back side of camera he attached Adafruit 2.2” TFT screen which comes with four navigation buttons. He also laser cut basic enclosure to make it look like real camera that can be taken anywhere for capturing photos and videos. Continue reading

E-ink display for Raspberry Pi

Raspberry Pi is a powerful but small Linux based computer board that gained its popularity in the hobby world. It has everything you need to build a computer except display. Since there are no DSI based display modules available, people try to solve this problem in several ways. They use HDMI based displays, composite video, serial monitors. Probably most of small projects rely on GPIO where they plug in their custom boards with various types of LCDs. This seems to be OK, but running such displays usually require additional driver/software to run and it occupies I/O pins, that can be used for other purposes. While we are waiting for official Raspberry Pi DSI display we have to deal with those workarounds. The choice is really big. You can find may types and sizes of displays driven through GPIO. Percheron Electronics Ltd are running kickstarter campaign where they offer to give a shot with their offered e-ink display solution. It comes on a module board that plugs in to Pi’s GPIO. Display resolution is 264×176. The main advantage of using such… Continue reading