IT Log

Record various IT issues and difficulties.

Month: February 2025


  • What Does “Request Timed Out” Mean

    Understanding “Request Timed Out”: A Comprehensive Explanation When encountering the error message “Request Timed Out,” it signifies an issue in the communication between your device (client) and the remote server. This error occurs when the client does not receive a response from the server within a specified timeframe, leading to the timeout. Causes of Request…


  • Assembly Language: How Direct Addressing Becomes Assignment

    Direct addressing in assembly language involves using a name to refer to a memory location, which is then translated into an assignment operation during program execution. Here’s how this process unfolds: Definition and Usage: When a variable or label (e.g., number dw 1234) is defined, it is assigned a specific memory address by the assembler.…


  • Using the IF function to return ‘pass’ if two cell values are within range, ‘fail’ otherwise, and leave blank if cells are empty.

    To solve the problem of returning ‘pass’ when two cell values are within a specified range, ‘fail’ otherwise, and leaving it blank if either cell is empty, we can use Excel’s IF function with nested logical functions. Here’s how to approach it: Check for Empty Cells: Use the IF function combined with OR(ISBLANK(cell1), ISBLANK(cell2)) to…


  • The N32G435CB returns an extra 1-byte data: 0xc5, which we have never sent. Could anyone explain why this happens

    To address the issue where the N32G435CB microcontroller returns an extra byte of data (0xC5) that was never sent, I systematically analyzed both hardware and software aspects. Hardware Connection Check: I verified all connections, particularly the SPI lines (SCK, MISO, MOSI), ensuring they were correctly soldered without any physical damage or misalignment. Power Supply Analysis:…


  • The stack size of XDATA is set to 0x1FF.

    The stack size of XDATA being set to 0x1FF indicates that a significant portion (256 bytes) of external data memory is allocated for the stack. This configuration is crucial in embedded systems using microcontrollers like the Intel 8051, where memory management is critical. Understanding Stack Size: The stack size refers to the amount of memory…


  • How to Select a Suitable Cloud Service Provider

    Selecting a suitable cloud service provider (CSP) requires a systematic approach to ensure it meets your business needs. Here’s a structured guide to help you through the process: 1. Define Your Requirements Understand Needs: Clearly define your business objectives, expected growth, and specific technical requirements. Assess Workload Characteristics: Consider scalability, performance, security, and compliance needs.…


  • What does the error “CE_SDK (CE_ARCH)” mean during compilation of the Qt toolchain for Windows CE 2013 It has been an issue.

    When encountering the error “CE_SDK (CE_ARCH)” during the compilation of the Qt toolchain for Windows CE 2013, it typically indicates an issue with the SDK or architecture configuration in your build environment. Here’s a detailed approach to resolve this: Review SDK Installation: Ensure that the necessary Windows CE 2013 SDKs are correctly installed on your…


  • CreateFile returns INVALID_HANDLE_VALUE issue

    When encountering the issue where CreateFile returns INVALID_HANDLE_VALUE, it’s essential to systematically diagnose and resolve the problem. Here is a structured approach based on the thought process: 1. Parameter Validation File Name (lpFileName): Ensure the file name is correctly specified, including the full path if necessary. Verify that the path exists or can be created.…


  • STM32F429 Power-off and Power-on Failure

    Investigating and Solving the STM32F429 Power-off and Power-on Failure In addressing the issue of power-off and power-on failures in an STM32F429 microcontroller, a systematic approach is essential to identify and rectify the root cause. Here’s a detailed analysis: Understanding the Problem: The primary symptom is that after powering off and then re-powering the system, the…


  • Window Flashes in Openbox

    To address the issue of window flashing in Openbox, a systematic approach was taken: Update Graphics Drivers: Checked for and installed the latest graphics drivers, ensuring no outdated versions were causing the issue. Disable Xcompmgr: Identified that Xcompmgr might be interfering with window management. Disabled it temporarily to test if the flashing stopped. Adjust Monitor…


  • Urgently Need Help! How to Resolve the Frequent Session Timeouts of Zookeeper Client and Broker Failure to Connect Triggering Automatic Shutdown

    To address the frequent session timeouts in your Zookeeper setup and prevent automatic broker shutdowns, follow this structured approach: Review Configuration Settings: Examine tickTime to ensure it’s set appropriately for your environment. Adjust if necessary to avoid premature client disconnections. Check other relevant configuration parameters on both server and client sides to ensure they align…


  • “What does ‘unable to locate package’ mean”

    The error message “unable to locate package” typically occurs when a package manager cannot find the requested software package. Here are the key points to consider and steps to resolve this issue: Typographical Error: Ensure the package name is correctly spelled and matches the exact name available in repositories. Incorrect Repository: Verify that the correct…


  • How to extract part of a string from a sequence of numbers

    To extract a specific part of a string embedded within a sequence of numbers, we can use regular expressions to identify transitions from numeric characters to non-numeric ones. Here’s how you can achieve this: Problem Understanding: Identify the substring that lies between sequences of numbers. For example, in “123abc456”, the desired extraction is “abc”. Regular…


  • How to filter out data without specific keywords

    To filter out data without specific keywords efficiently, follow these steps: Understand Data Structure: Determine if your data is in a text file, CSV, database, or another format. This influences how you access each entry. Identify Keywords: Define whether the criteria are substrings within fields or exact category matches. Choose Programming Language: Use appropriate methods…


  • Why do the numbers pulled down using the VLOOKUP function appear equal

    When using the VLOOKUP function in Excel, if the numbers pulled down appear equal, it may be due to several reasons: Data Consistency: The values being looked up might be consistent across rows, causing the same result to display each time. Absolute References: If the formula uses absolute references (e.g., $A$1), Excel will reference the…


  • What is the meaning of error code 405

    The HTTP status code 405 indicates that the method requested is not allowed for the specified resource on the server. This error occurs when a client sends a request using an HTTP method (such as GET, POST, PUT, DELETE) that the server does not support or allow for the targeted URL. Understanding the Error: HTTP…


  • What does “application error” mean

    Understanding the Term “Application Error” The term “application error” refers to an issue or malfunction that occurs within a software application during its operation. This type of error can disrupt normal operations, leading to unexpected behavior, crashes, or incomplete tasks. Definition and Context: An “application error” is any unintended occurrence in software that prevents it…


  • Is MB capable of recognizing and processing the boolean data type

    Based on the analysis and assuming MB refers to a programming language or tool that supports standard data types: Answer: MB is capable of recognizing and processing the boolean data type. Boolean values (true/false) are typically supported in most modern programming languages and tools, allowing for effective use in conditional logic and data handling.


  • How to write the condition in Tongdaxin formulas to execute DRAWKLINE(H, O, L, C) when the code does not start with 880

    To address the problem of executing DRAWKLINE(H, O, L, C) in Tongdaxin formulas only when the code does not start with 880, follow these steps: Access Current Code: Use the CODE() function to retrieve the current stock code. Extract Prefix: Extract the first three characters of the code using LEFT(CODE(), 3). Comparison: Compare the extracted…


  • Solving Fuzzy Text in QGraphicsView When Displaying Images

    To address the issue of fuzzy text displayed on a QGraphicsView when rendering images, I conducted an extensive investigation and implemented several solutions. Solution: Rendering Settings Adjustment: Anti-Aliasing Enablement: The primary cause of the fuzzy text was identified as insufficient anti-aliasing in the rendering process. By enabling high-quality anti-aliasing using setRenderHint(QGraphicsView::Antialiasing), the text sharpness improved…


  • Error 0x80070091: Directory Not Empty – How to Fix

    To resolve the error 0x80070091 “Directory Not Empty,” follow these steps systematically: Identify the Directory: Locate the directory that is causing the error. Manual Deletion: Delete all files within the directory manually. Remove any subdirectories by recursively deleting their contents. Check Permissions: Right-click the directory, select “Properties,” and navigate to the “Security” tab. Ensure you…


  • In Using PyWebView, HTML Page Data Requests Always Throw an Error: TypeError: Cannot Read Properties of Undefined (Reading ‘Api’)

    When encountering the error TypeError: Cannot read properties of undefined (reading ‘Api’) in PyWebView, it’s crucial to systematically diagnose and resolve the issue. Here’s a structured approach: Verify JavaScript API Calls: Ensure all API calls within your HTML/JS code correctly reference the webView.Api object. Check for typos or incorrect references. Check WebView Initialization: Confirm that…


  • How to Fix ‘sbit’ Errors When Writing C51 Code in CLion

    To address the ‘sbit’ errors in C51 code within CLion, follow these structured steps: Understand the Context: The ‘sbit’ keyword is specific to C51 compilers like Keil or IAR Systems and isn’t recognized by standard GCC. Install C51 Compiler: Download a compatible C51 compiler toolchain (e.g., from Keil, Dev-C++, or SDCC). Extract the compiler binaries…


  • Can Delphi Create .NET-like DLL Libraries

    Creating .NET-like DLL libraries with Delphi requires a deeper understanding of its capabilities and the target environment. Here’s a structured explanation: 1. Understanding Delphi and Its Compiling Nature Delphi Overview: Delphi is primarily used for Windows development, compiling into native code (Win32 or x64) that runs directly on the operating system without needing an external…


  • Is there an expert or senior developer regarding the Feign call interface returning a 400 Bad Request error during POST

    To address the issue where a Feign client returns a 400 Bad Request error during a POST request, follow these steps: Inspect Request Headers: Ensure all necessary headers are correctly set, including Content-Type and Authorization. Verify that any required authentication tokens are properly included. Review Request Body: Check the structure of your request body. Confirm…


  • Why can’t I find the main class in Java

    To resolve the issue of not finding the main class in your Java application, follow these steps: Verify the Main Method: Ensure that your main class contains a public static void main(String[] args) method. This is mandatory for any Java application. Check Package Configuration: If your class is part of a package, run the application…


  • Why does a 404 error occur before the execution of Global’s Application_BeginRequest when rewriting URLs in web services

    To resolve the issue of a 404 error occurring before the execution of Global::Application_BeginRequest when rewriting URLs in web services, follow these steps: Review URL Rewrite Configuration: Examine the <rewrite> section in your web.config file to ensure that all rewrite rules are correctly defined. Check for any syntax errors or incorrect conditions in your rewrite…


  • Exploring the reasons for differences in writing and results of CRC verification in modbusrtu returned data

    To address the discrepancy in CRC verification between written and returned data in Modbus RTU communication, a systematic approach is essential. Here’s how I would tackle this issue: Understand Modbus RTU Frame Structure: Begin by thoroughly understanding the structure of a Modbus RTU frame, which includes device address, function code, data field, and CRC. Verify…


  • XML and UG Secondary Development – Save Parameter Configuration

    To address the problem of saving parameter configurations to XML and integrating them with Universal Grid (UG) for secondary development, we can follow a structured approach. Here’s how I would proceed: Define Parameter Structure: Create an XML schema that defines the structure of the parameters. For instance: <configuration> <section name=”Database”> <parameter name=”ConnectionString”>Value</parameter> <parameter name=”Timeout”>30</parameter> </section>…


  • How to UsecreateTimeSeriesEngine in DolphinDB for Time Series Metrics

    To effectively utilize the createTimeSeriesEngine function in DolphinDB for time series metric calculations, follow these steps: Install and Set Up DolphinDB: Ensure that you have installed DolphinDB and set up your environment to run its commands or scripts. Understand Function Parameters: Familiarize yourself with parameters like input table name, time column, value columns, and the…