An easily overlooked overflow problem in 8-bit microcontrollers
Reference address：An easily overlooked overflow problem in 8-bit microcontrollers
example:
uint16 wTmp ;
uint8 x ;
x=2;
wTmp = (uint16)(x*150);
Everyone, is there any problem with the above multiplication? What is the value of wTmp?
I believe many people will say without thinking, no problem! wTmp=300 .
OK, here comes the problem! Let me tell you, the result is actually wTmp=44. I won't explain it in detail here, please think about it yourself,
and be careful
next time you encounter a similar situation !
Correct way to write:
x=2;
wTmp = (uint16)(x)*150; //wTmp=300
Previous article：Transplantation of Lua in MCU
Next article：The running process of a program in a single chip microcomputer
- Popular Resources
- Popular amplifiers
ISL28345FBZ-T7A
Recommended Content
Latest Microcontroller Articles
- Download from the Internet--ARM Getting Started NotesA brief introduction: From today on, the ARM notebook of the rookie is open, and it can be regarded as a place to store these notes. Why publish it? Maybe you are interested in it. In fact, the reason for these notes is ...
- Learn ARM development(22)Turning off and on interrupts Interrupts are an efficient dialogue mechanism, but sometimes you don't want to interrupt the program while it is running. For example, when you are printing something, the program suddenly interrupts and another ...
- Learn ARM development(21)First, declare the task pointer, because it will be used later. Task pointer volatile TASK_TCB* volatile g_pCurrentTask = NULL;volatile TASK_TCB* vol ...
- Learn ARM development(20)With the previous Tick interrupt, the basic task switching conditions are ready. However, this "easterly" is also difficult to understand. Only through continuous practice can we understand it. ...
- Learn ARM development(19)After many days of hard work, I finally got the interrupt working. But in order to allow RTOS to use timer interrupts, what kind of interrupts can be implemented in S3C44B0? There are two methods in S3C44B0. ...
- Learn ARM development(14)
- Learn ARM development(15)
- Learn ARM development(16)
- Learn ARM development(17)
He Limin Column
Microcontroller and Embedded Systems Bible
Professor at Beihang University, dedicated to promoting microcontrollers and embedded systems for over 20 years.
MoreSelected Circuit Diagrams
MorePopular Articles
- Innolux's intelligent steer-by-wire solution makes cars smarter and safer
- 8051 MCU - Parity Check
- How to efficiently balance the sensitivity of tactile sensing interfaces
- What should I do if the servo motor shakes? What causes the servo motor to shake quickly?
- 【Brushless Motor】Analysis of three-phase BLDC motor and sharing of two popular development boards
- Midea Industrial Technology's subsidiaries Clou Electronics and Hekang New Energy jointly appeared at the Munich Battery Energy Storage Exhibition and Solar Energy Exhibition
- Guoxin Sichen | Application of ferroelectric memory PB85RS2MC in power battery management, with a capacity of 2M
- Analysis of common faults of frequency converter
- In a head-on competition with Qualcomm, what kind of cockpit products has Intel come up with?
- Dalian Rongke's all-vanadium liquid flow battery energy storage equipment industrialization project has entered the sprint stage before production
MoreDaily News
- Allegro MicroSystems Introduces Advanced Magnetic and Inductive Position Sensing Solutions at Electronica 2024
- Car key in the left hand, liveness detection radar in the right hand, UWB is imperative for cars!
- After a decade of rapid development, domestic CIS has entered the market
- Aegis Dagger Battery + Thor EM-i Super Hybrid, Geely New Energy has thrown out two "king bombs"
- A brief discussion on functional safety - fault, error, and failure
- In the smart car 2.0 cycle, these core industry chains are facing major opportunities!
- The United States and Japan are developing new batteries. CATL faces challenges? How should China's new energy battery industry respond?
- Murata launches high-precision 6-axis inertial sensor for automobiles
- Ford patents pre-charge alarm to help save costs and respond to emergencies
- New real-time microcontroller system from Texas Instruments enables smarter processing in automotive and industrial applications
Guess you like
- Problems connecting Bluetooth module with CC2541
- Matter Development Guide (VI): Network Configuration and Lighting-App Examples
- Based on FOC5.3 library IHM07 self-made board BLDC/PMSM motor drive: schematic/device library/reference program/training materials/delivery...
- 【EasyARM-RT1052 Review】+ SDRAM Memory Management
- Usage of MSP430F5438 internal delay function
- MCU Selection
- Qianao driving recorder disassembly-communication module
- Micropython windows compilation error
- 【GD32307E-START】Development environment construction + some problems encountered
- Introduction to Microcontroller (MCU) Architecture
京公网安备 11010802033920号