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Claude Code for Beginners: Step-by-Step AI Coding Tutorial

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 Artificial Intelligence is changing how developers write software. From generating code to fixing bugs and explaining complex logic, AI tools are becoming everyday companions for programmers. One such powerful tool is Claude Code , powered by Anthropic’s Claude AI model. If you’re a beginner or  an experienced developer looking to improve productivity, this guide will help you understand  what Claude Code is, how it works, and how to use it step-by-step . Let’s get started. What is Claude Code? Claude Code is an AI-powered coding assistant built on top of Anthropic’s Claude models. It helps developers by: Writing code from natural language prompts Explaining existing code Debugging errors Refactoring code for better readability Generating tests and documentation In simple words, you describe what you want in plain English, and Claude Code helps turn that into working code. It supports multiple programming languages, such as: Python JavaScri...
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How to Decode TLV Quickly

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TLV format consists of three components: Tag, Length, and Value. In credit card and financial transactions, the TLV protocol utilizes this structure. Below, you will find tips for quickly decoding TLV data. 


TLV Format



According to IBM, the tag tells what type of data it is. The length field denotes the length of the value, and the value is the actual value.


Structure of TLV.


TLV comprises three field values.


  1. Tag
  2. Length
  3. Value


How to Decode TLV


The EMV labs developed tags that are part of the EMV protocol. Each tag has a unique meaning. The Tag and Length together take 1 to 4 bytes of memory.

1. The Best example for TLV.


Below is the method for decoding the EMV tag. The first part of the TLV format is TAG. The second part is LENGTH, and finally, the value.


Syntax of EMV tag:


[Tag][Value Length][Value] (ex. "9F4005F000F0A001")


where, 


Tag Name = 9F40


Value Length (in bytes) = 05 


Value (Hex representation of bytes. Example, "F0" – 1-byte) = F000F0A001


Finally, what is 9F40 tag? The EMV company assigns a value to it. Check out the complete list of EMV Tags and meanings.



2. How to read the TLV


Let me elaborate on the memory the EMV tag takes. The breakup of memory allocation is as follows.

 

Tag: 1 or 2 bytes.


Length: 05


Value length:


F0-00-F0-A0-01 ==> 5 Bytes


The F0 is the HEX value of length 1. So the total length of the value altogether is 5 bytes.


F0+00+F0+A0+01= Total 5 bytes



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