Getting started with Raspberry Pi

Raspberry Pi is a small, low powered motherboard contains 512 RAM, combined CPU and GPU. It has LAN, 2 USB, HDMI input, Audio Out, SD Card reader and S-Video connectors.

We can have many Linux distribution OS on it. To configure, we just need to attach SD Card to it. SD Card could range from class 4 to class 10. In some cases Raspberry Pi could support less then class 4 cards too. It could be powered through mini USB mobile charger.

Let's get started with installing OS on SD Card. There are various ways to install OS. Like we can download OSes through http://www.raspberrypi.org/downloads and follow the instructions given on it. There is something BerryBoot multi-boot loader through which we can have more then one OS on Raspberry Pi and boot OS according to our need. http://www.berryterminal.com/doku.php/berryboot instructions could be followed to install OS with very simple steps. You need to have internet connection on Raspberry Pi to install OS. It could be done by connecting through LAN or some Raspberry PI WiFi dongle.

Give it a try to Raspbian wheezy and XBMC OS. Raspbian wheezy is similar to any other Linux distribution OS. Through XBMC we can convert normal TV into smart TV or can have HTPC. It is able to play Full HD video and also it could be controlled through mobiles, slates or some TV remotes. XMBC is having tons of features through it's various add-ons.

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Using Redis distributed cache in dotnet core with helper extension methods

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C# Response files

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Trim text in MVC Core through Model Binder

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Blazor 0.5.0 Interop JavaScript from C# and C# to JavaScript call

Blazor provides two-way communication from JS to C# and C# to JS which is called Interop. The version upgrade to Blazor 0.5.0 changed the approach in interactions between cshtml and JS files. The newer version simplifies JS calling by avoiding pre-registration of JS function. In this article, we would see how to call a JS method by passing multiple parameters from cshtml and parameterized call from JS to cshtml. The scenario that is used in this article has a Kendo AutoComplete to search book and populate information based on the selection. An example of a call to JS from cshtml await JSRuntime.Current.InvokeAsync<string>( "searchBook.Init", "#SearchTitle", new DotNetObjectRef(this)); Takeaways from the above example: - JSRuntime.Current give environment to execute out-process JS. - InvokeAsync is a function that would allow executing the JS function. - The searchBook.Init is a JS function call, we would see it in details in the second sec...

Channel, ChannelReader and ChannelWriter to manage data streams in multi-threading environment

I came across Channel class while working with SignalR which looks really interesting. By looking into NuGet packages ( https://www.nuget.org/packages/System.Threading.Channels ), it seems just 4 months old. The Channel class provides infrastructure to have multiple reads and write simuletensely through it's Reader and Writer properties. This is where it is handy in case of SignalR where data streaming needs to be done but is not just limited to that but wherever something needs to be read/write/combination of both in a multi-threading environment. In my case with SignalR, I had to stream stock data at a regular interval of time. public ChannelReader<StockData> StreamStock() { var channel = Channel.CreateUnbounded<StockData>(); _stockManager.OnStockData = stockData => { channel.Writer.TryWrite(stockData); }; return channel.Reader; } The SignalR keeps return type of ChannelReader<StockData> open so that whatev...

Kendo MVC Grid DataSourceRequest with AutoMapper

Kendo Grid does not work directly with AutoMapper but could be managed by simple trick using mapping through ToDataSourceResult. The solution works fine until different filters are applied. The problems occurs because passed filters refer to view model properties where as database model properties are required after AutoMapper is implemented. So, the plan is to intercept DataSourceRequest and modify names based on database model. To do that we are going to create implementation of CustomModelBinderAttribute to catch calls and have our own implementation of DataSourceRequestAttribute from Kendo MVC. I will be using same source code from Kendo but will replace column names for different criteria for sort, filters, group etc. Let's first look into how that will be implemented. public ActionResult GetRoles([MyDataSourceRequest(GridId.RolesUserGrid)] DataSourceRequest request) { if (request == null) { throw new Argume...

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A wrapper implementation for Kendo Grid usage

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