Ans the ques B

1. Answer all the questions given below (a) Explain the difference between edge triggered and level triggered interrupt by sketch. Where the starting address of the memory location of every interrupt is stored? [2.5+2.5] (b) Consider the following 8051 interfacing problem. Crystal frequency: 11.059MHz. The LED D8 will light up with every key press as shown below. [1+1+1+1+1] 45V C3 10uF R2 10K R1680 U1 XTAL1 40 VCC LED-YELLOW XTAL2 12MHz PO DADO PO.1/AD1 PO 2/AD2 PO.3/AD3 PO 4/AD4 PO 5/ADS PO 6/AD6 PO.7/AD7 D8 Hok 9 RST 32 CRYSTAL 21 C1 22pF C2 13 22pF R9 10k 29 30 31 PSEN ALE EA P2.0/AB P2.1/A9 P22/A10 P2.3/A11 P2.4/A12 P2.5/ A13 P2.6/A14 P2.7/A15 28 10 P1.0 P1.1 P12 P1.3 P1.4 P1.5 P1.6 P1.7 AT89C51 P3.0/RXD P3.1/TXD P32 INTO P3 3/INT1 P3.4/TO P3T P3.6/WR P3.7/RD 12 13 14 15 GND 20 i) ii) Initialize IE register for external interrupt at INTO Initialize TCON register for the appropriate type of interrupt Declare and define the interrupt service routine Access and configure relevant pin as needed Call back action in the main function as needed iv) v)