Ppi

2. 82C55
(PPI)

10. 0 0 0 0 0 0 0
1
For PA / OUT
80h
For PA / IN
90h

12. 0 1 0 0 0 0 0
1
For PA / OUT
A0h
For PA / IN
B0h

14. Strobed Output
WR
AD0-7
PPI

15. Strobed Input
RD
AD0-7
PPI

16. CONT: MOV DX,5004h ;PC Address
IN AL,DX
TEST AL,20h
JE IBF
JMP CONT
IBF: MOV DX,5000h ;PA Address
IN AL,DX
JMP CONT

17. CONT: MOV DX,5004h ;PC Address
IN AL,DX
TEST AL, 02h
JNE OBE
JMP CONT
OBE: MOV DX,5002h ;PB Address
MOV AL,DATA
OUT DX,AL
JMP CONT

18. Eg. PC0= 0 0 0 0 0
Eg. PC0= 1 1
CONT: MOV DX,5006h ;CW Address
MOV AL,0
OUT DX,AL
MOV AL,1
OUT DX,AL
MOV AL,2
OUT DX,AL
INTERUPT ENABLE FLAGS IN MODE 1 AND 2

20. 1 0 0 0 0 0 0
1
For PA / M2
PB / M0 – O/P
C0h
For PB / I/P
C4h

24. PORT
DATA

25. CONT: MOV DX,5004h ;PC Address
IN AL,DX
TEST AL,20h
JE IBF
TEST AL,80h
JNE OBE
JMP CONT
OBE: MOV DX,5000h ;PA Address
MOV AL,DATA
OUT DX,AL
JMP CONT
IBF: MOV DX,5000h ;PA Address
IN AL,DX
JMP CONT

28. 1. Draw the address decoder for an 8086
Microprocessor system with a single PPI putting
the control word address = 3FD6h using discrete
components.
2. Draw the address decoder for an 8086
Microprocessor system with a single PPI putting
port B address = 6FD2h using 74LS138 decoder.

29. 1. Write a program to read data from portA,
complement it then send it to portB using mode1.
Let the control word address = 0306h.
2. Write a program to read data from portA, add the
contents of AH to it then send it again to portA
using mode2.
Let the portA Address = 0306h.