B.Voc Mechatronics PCCoE

 Unit 5: 8051 Interrupts and Interfacing Applications 1. Explain the concept of interrupts in the 8051 microcontroller. (6 Marks) Interrupts are events that temporarily halt the main program execution in the 8051. They allow external devices or internal events to signal the microcontroller for attention. The microcontroller then pauses the current task, saves its state, and executes an Interrupt Service Routine (ISR) specific to the interrupt source. Once the ISR finishes, the microcontroller restores its state and resumes the main program from where it left off.       2. Describe the Interrupt handling mechanism in the 8051. (6 Marks) The 8051 has five interrupt sources: INT0  and  INT1:  External hardware interrupts on pins P3.2 and P3.3. TF0  and  TF1:  Timer overflow interrupts from Timer/Counter 0 and 1. RI/TI:  Serial communica...

Unit 4: 8051 Timers and Serial Communication Question 1 (6 Marks): Explain the concept of timers and counters in the 8051 microcontroller and their different modes of operation. Answer: The 8051 has two built-in 16-bit timers/counters (Timer0 and Timer1). These timers can be configured to operate in different modes to perform various timing and counting functions. Modes of Operation: Mode 0 (13-Bit Timer): In this mode, both Timer0 and Timer1 operate together as a single 13-bit timer. When the combined timer reaches its maximum value (8191), it overflows, generating an interrupt (if enabled). Mode 1 (16-Bit Timer): In this mode, Timer0 or Timer1 acts as an independent 16-bit timer. When the timer reaches its maximum value (65535), it overflows, generating an interrupt (if enabled). Mode 2 (Auto-Reload): This mode allows automatic reloading of a preload value into the timer after an overflow occurs. This is useful for genera...

 Unit 3: 8051 Interfacing and Programming Question 1 (6 Marks): Explain the concept of the stack in the 8051 microcontroller and PUSH & POP. Answer: A stack is a linear data structure in which the insertion of a new element and removal of an existing element takes place at the same end represented as the top of the stack. Stack is a section of RAM used by the CPU to store the information temporarily The register used to access the stack is called the SP (stack pointer) register. The ‘PUSH’ is used for taking the values from any register and storing in the starting address of the stack pointer. POP is used for placing the values from the stack pointer’s maximum address to any other register’s address To implement the stack, it is required to maintain the pointer to the top of the stack, which is the last element to be inserted because we can access the elements only on the top of the stack. LIFO (Last In First Out): This strategy states that the element that is inserted last wil...

 Unit 2: 8051 Instruction Set Q.IMP Write assembly language program on subroutine using loop: Multiply 15 by 10 using the technique of a repeated addition (7 Marks) Code snippet ; Main program MOV A, #15 ; Load value 15 into accumulator CALL MULTIPLY ; Call the subroutine to multiply by 10 ; After subroutine returns, the result will be in accumulator A ; (Accumulator will contain 150)   ; Rest of your program code...   ; Subroutine definition MULTIPLY: MOV R0, #10 ; Set counter (R0) to 10 for 10 repetitions LOOP: ADD A, #15 ; Add 15 to accumulator (repeated addition) DJNZ R0, LOOP ; Decrement counter and loop if not zero   ; After the loop, A will have the result (15*10) RET ; Return from the subroutine Question 1 (6 Marks): Explain the concept of addressing modes in the 8051 instruction set. Provide examples for different addressing modes. Answer: Addressing modes specify how the 8051 microcontroller locates the data operan...

Unit 1: 8051 Microcontroller (General Questions and Answers) Question 1 (6 Marks): Differentiate between a microprocessor and a microcontroller. Question 2 (6 Marks): Briefly describe the 8051 microcontroller architecture with the help of a block diagram. Answer: The 8051 microcontroller follows the Harvard architecture, separating program memory from data memory. Key components include: Central Processing Unit (CPU): Processes instructions, performs calculations, and controls program flow. It consists of: Arithmetic Logic Unit (ALU) for arithmetic and logical operations. Control Unit (CU) for fetching, decoding, and executing instructions. Registers for temporary data storage and program control. Question 3 (6 Marks): Explain the functionalities of any three 8051 microcontroller pins with the help of a pin diagram. Answer: Port 0 (P0.0 - P0.7): 8-bit bidirectional I/O port. Each pin can be configured as input or output for connecting with external devices (sensors, LEDs, etc.). ALE (A...

    UNIT 3 : Corrosion   Q1) Explain any five factors affecting corrosion. Position in Galvanic Series: More active metals corrode faster when in electrical contact in a conducting medium. Relative Areas of Anode and Cathode: Corrosion rate depends on the ratio of cathodic to anodic area. a larger anodic area minimizes corrosion. Purity of Metal: Impurities create galvanic cells, leading to corrosion. Temperature: Higher temperatures speed up both atmospheric and electrochemical corrosion. Conductivity of Corroding Medium: The electrical conductivity of the medium affects the rate of electrochemical corrosion. Higher conductivity results in faster corrosion.         Q2) Define Hot dipping. Explain coating method with neat labelled diagram to protect metal from corrosion and give applications. Hot Dipping: Hot dipping is a method that in...