Showing posts with label system. Show all posts
Showing posts with label system. Show all posts

Relational Algebra - Selection, Projection, Joins etc

The relational algebra defines a set of operations on relations, paralleling the usual algebraic operations such as addition, subtraction etc which operate on numbers.The relational algebra operations take one or two relations (tables) as input and return a relation as output. This post we discuss the following relational operations:
  1. Selection (σ)
  2. Projection (π)
  3. Cartesian product
  4. Joins

Selection Operation (σ)

C Program to Display and Set System Time and Date Using 8086 Interrupts

This is a C Program to Display and Set System Time and Date Using 8086 Interrupts. Interrupt number 21 (in hexadecimal) is used to:
C program to get system time and date and also to set it using 8086 interrupt INT 21 interrupt 0x21 21h int86() function call interrupts in C program
Output of c Program to get and set system time and date 

  • Get System time
  • Set System time
  • Get System Date
  • Set System Date
To Get system date:
- Call interrupt 0x21 (hexadecimal) 
- AH (higher byte of accumulator) should be made equal to 2A (hex) before calling interrupt
Output: