Jan 24, 2018 - The Atmel AT89S51 is an 8051 based Full Static CMOS controller with Three-Level Program Memory Lock, 32 I/O lines, 2 Timers/Counters,. Circuit and Program to Interface MT8870 with AT89S51 1.0. Decoding the DTMF signals from the telephone line with circuit diagram.

This section describes how to interface an DTMF decoder to the microcontroller AT89S51/52
and to display the digits over the seven segment display.
The circuit also has an Ring sensor which is not used in the program.
Program

1. Q3 EQU P3.1
2. Q1 EQU P3.3
3. DIS_B EQU P0.1
4. DIS_D EQU P0.3
5. DIS_F EQU P0.5
6. ORG 20H ; Bit adressable memory
7. DTMF: DS 1
8. D1 BIT DTMF.1
9. D3 BIT DTMF.3
10. ;-------------------------------------
11. ;-------------------------------------
12. MOV SP,#60H
13. CALL DISP ;Display - symbol on display
14. CALL READ ;Read Data
15. CALL DISP ;Display Dialled Data
16. AJMP TOP ;Repeat the function
17. ; READ DTMF TONES
18. READ:
19. SETB Q0
20. SETB Q2
21. JNB Q0,VB1
22. VB1: JNB Q1,VB2
23. VB2: JNB Q2,VB3
24. VB3: JNB Q3,VB4
25. VB4: RET
26. ;&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&
27. ;&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&
28. CJNE R2,#00H,AAS1
29. CLR DIS_B
30. CLR DIS_D
31. CLR DIS_F
32. RET
33. CLR DIS_B
34. SETB DIS_A
35. SETB DIS_E
36. SETB DIS_G
37. AS2: CJNE R2,#02H,AS3
38. CLR DIS_B
39. CLR DIS_E
40. SETB DIS_C
41. RET
42. CLR DIS_A
43. CLR DIS_C
44. CLR DIS_G
45. SETB DIS_F
46. AS4: CJNE R2,#04H,AS5
47. CLR DIS_C
48. CLR DIS_G
49. SETB DIS_D
50. RET
51. CLR DIS_A
52. CLR DIS_D
53. CLR DIS_G
54. SETB DIS_E
55. AS6: CJNE R2,#06H,AS7
56. CLR DIS_C
57. CLR DIS_E
58. CLR DIS_G
59. RET
60. CLR DIS_A
61. CLR DIS_C
62. SETB DIS_E
63. SETB DIS_G
64. AS8: CJNE R2,#08H,AS9
65. CLR DIS_B
66. CLR DIS_D
67. CLR DIS_F
68. RET
69. CLR DIS_A
70. CLR DIS_C
71. CLR DIS_F
72. SETB DIS_E
73. AS10: CJNE R2,#15H,AS11 ;symbol for -
74. SETB DIS_B
75. SETB DIS_D
76. SETB DIS_F
77. RET
78. CJNE R2,#16H,AS12 ;switch off all disp
79. SETB DIS_B
80. SETB DIS_D
81. SETB DIS_F
82. RET
83. RET
84. ;**********************************************************

Voltmeter using 8051.

A simple 0-5V voltmeter using 8051 is shown in this article. This digital voltmeter has a sensitivity of 200mV which is a bit low but this project is meant for demonstrating how an ADC and seven segment display can be interfaced to 8051 to obtain a digital readout of the input voltage. A 31/2 digit high end voltmeter will be added soon. ADC0804 is the ADC and AT89S51 is the controller used in this project. Before attempting this project, go through these projects Interfacing ADC to 8051and Interfacing seven segment display to 8051which will give you a good idea on the basics.

Circuit diagram.

About the circuit.

In the circuit Vref/2 (pin9) of the ADC is left open and it means that the input voltage span can be o to 5V and the step size will be 5/255 = 19.6mV. The equation for the digital output of ADC0804 is Dout = Vin/Step size. In this circuit, for an input voltage of 1V the digital output will be 1/19.6mV = 51 and so the binary equivalent of 51 ie 00110011. Misteri gunung merapi video. Digital output of the ADC is interfaced to P1.0 of the microcontroller. Control signals for the ADC ie CS, RD, WR and INTR are available from the P3.7, P3.6, P3.5 and P3.4 pins of the microcontroller respectively. 2 digit multiplexed seven segment display is interfaced to Port0 of the microcontroller. Control signals for the display driver transistors Q1 and Q2 are obtained from P3.2 and P3.1 of the microcontroller. Push button switch S1, capacitor C2 and resistor R10 forms a debouncing reset circuitry.

Program.

ORG 00H
MOV P1,#11111111B
MOV P0,#00000000B
MOV P3,#00000000B
MOV DPTR,#LABEL
MAIN: CLR P3.7
SETB P3.6
CLR P3.5
SETB P3.5
WAIT: JB P3.4,WAIT
CLR P3.7
CLR P3.6
MOV A,P1
MOV B,#10D
DIV AB
MOV B,#2D
MUL AB
MOV B,#10D
DIV AB
SETB P3.2
ACALL DISPLAY
MOV P0,A
ACALL DELAY
MOV P0,#10000000B
ACALL DELAY
MOV A,B
CLR P3.2
SETB P3.1
ACALL DISPLAY
MOV P0,A
ACALL DELAY
CLR P3.1
SJMP MAIN
DELAY: MOV R3,#02H
DEL1: MOV R2,#0FAH
DEL2: DJNZ R2,DEL2
DJNZ R3,DEL1
RET
DISPLAY: MOVC A,@A+DPTR
RET
LABEL: DB 3FH
DB 06H
DB 5BH
DB 4FH
DB 66H
DB 6DH
DB 7DH
DB 07H
DB 7FH
DB 6FH
END

About the program.

At first the program controls the ADC to produce a digital output corresponding to the input voltage.This digital output is scanned through P1.0 and is loaded to accumulator. Then the value in the accumulator is divided by 10 to omit the last digit. For example, let the input voltage be 4V. Then the corresponding digital output of the ADC will be 204D (D stands for decimal) .After the the division by 10, the value left in the accumulator will be 20D. This 20D is then multiplied by 2D which results in 40D. The next target of the program is to manipulate this 40D and make a 4.0 readout on the display. For this the 40D is again divided by 10D . This results in 4 inside accumulator and 0 inside B register. Then the program gets the digit drive pattern for 4 using the lookup table , puts this pattern on Port 0 and activates Q1. After 1 ms delay 10000000B is loaded to P0 and this accounts for the dot. After a further 1ms delay Q1 is deactivated, content in B (ie 0) is moved to A, gets the correct digit drive pattern for 0 using the lookup table, puts this pattern on Port 0 and activates Q2. After a further 1ms delay Q2 is deactivated and the entire cycle is repeated.

DOWNLOAD Infinite Flight Simulator Mod apk all airports and planes unlocked for FREE. Infinite Flight Simulator Hacked [Unlocked Planes/Maps] Apk. How to download infinite flight with all. Download infinite flight mod map. Infinite Flight Simulator 18.04.0 Mod APK Download Description Infinite Flight offers the most comprehensive flight simulation experience on mobile devices, whether you are a curious novice or a decorated pilot.