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Controlling Audio Volume & Tone with a Remote Control

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Here is the project of controlling audio volume and audio tone (bass and treble) with a remote control designed using microcontroller AT89S52.It is a mono audio controller and to make it stereo similar circuits have to be made for the both LEFT and RIGHT channels. I have not connected the components in a PCB but I have tested the circuit in breadboard. It is working well.
 
COMPONENTS
1.         MICROCONTROLLER , AT89S52
2.         INFRARED RECEIVER, TSOP1738
3.         NPN TRANSISTORS
4.         CAPACITORS 
5.         RESISTORS
6.         POWER SUPPLY (+5V, +12V) DC
7.         CRYSTAL (11.0592 MHz)
 
The need of number of NPN TRANSISTORS, CAPACITORS, RESISTORS depend on the application of number of controls i.e. volume, bass or treble or all the three. Circuit for Controlling audio volume and tone using microcontroller
 

Volume Controller

 
OPERATION
VOLUME CONTROLLER
The input to the volume controller is an analog audio signal from sources like ipod, laptop, PC, microphone etc. The analog output should be fed to an audio amplifier. For each bit coming from the microcontroller at the base of each transistor, the resistor series is short circuited thus reducing the overall resistance between analog input terminal and analog output terminal. volume controller
 

Bass and Treble Controller

 
BASS AND TREBLE CONTROLLER
The circuit consists of a small signal audio amplifier with a feedback circuit. The controlling of bass (in case of bass controller) and treble (in case of treble controller) is done in the feedback part of the respective circuit. Here also analog input signals may be from the sources mentioned above.
Bass ControllerTrebble Controller
For controlling of all the three features at the same with the microcontroller, the output of the volume controller SHOULD be given as input to both the bass and treble controller and the output of the bass and treble controller are tied together and fed to an audio amplifier.
If any of the three controls i.e. volume, bass and treble is not to be used then the respective pins of the microcontroller should be left disconnected. 
 

Power Supply & Remote Control

 
POWER SUPPLY
During my experiment I have used both LMPS and SMPS as power supply but LMPS seems to be noise proof than SMPS. So I recommend to use LMPS specifically for this project.
 
REMOTE CONTROL
I have used a SAMSUNG DVD PLAYER REMOTE CONTROL. The model number is AH5900020E. The controls are arranged like among the lower buttons the left (decrease) & right (increase) are for BASS and up (increase) & down (decrease) are for TREBLE and the middle button is dedicated to MUTE. The buttons above them are for VOLUME, left for decrease & right for increase
Any remote control can be used with changes in the microcontroller program.

 

 

 

Project Source Code

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ORG 00H
 
IR                            EQU P0.0             ;IR RECEIVER CONNECTED HERE
CMNDCOUNT                    EQU R0
ADDRCOUNT                                     EQU R1
CMNDSTORE                                      EQU R2
ADDRSTORE                       EQU R3
TEMPVAR                            EQU R4
VOL                                        EQU P1                ;VOLUME CONTROLLER CONNECTED HERE
BASS                      EQU P3                ;BASS CONTROLLER CONNECTED HERE
TREBLE                  EQU P2                 ;TREBLE CONTROLLER CONNECTED HERE
VOLSTORE                           EQU       10H
 
CLR      00H
MOV      VOL, #01H
MOV      BASS, #01H
MOV      TREBLE, #01H
ORIGIN:
 
MOV      A, #00
CLR      C
MOV      CMNDCOUNT, #16H
MOV      ADDRCOUNT, #12
MOV      TEMPVAR, #00
JB       IR, $
ACALL    NINE
 
GETADDR:                                                                                           ;GETTING ADDRESS FROM REMOTE CONTROL
JNB      IR, $
ACALL    FIVESIX
JNB      IR, CO
ACALL    FIVESIX
ACALL    FIVESIX
SJMP     CI
CO:
MOV      A, TEMPVAR
CLR      C
RLC      A
MOV      TEMPVAR, A
SJMP     ASTORE
CI:
MOV      A, TEMPVAR
SETB     C
RLC      A
MOV      TEMPVAR, A
SJMP     ASTORE
ASTORE:
DJNZ     ADDRCOUNT, GETADDR
MOV      A, TEMPVAR
MOV      ADDRSTORE, A
MOV      TEMPVAR, #00
 
 
GETCMND:                                                                                         ;GETTING COMMAND FROM REMOTE CONTROL
JNB      IR, $
ACALL    FIVESIX
JNB      IR, SO
ACALL    FIVESIX
ACALL    FIVESIX
SJMP     SI
SO:
MOV      A, TEMPVAR
CLR      C
RLC      A
MOV      TEMPVAR, A
SJMP     CSTORE
SI:
MOV      A, TEMPVAR
SETB     C
RLC      A
MOV      TEMPVAR, A
SJMP     CSTORE
CSTORE:
DJNZ     CMNDCOUNT, GETCMND
MOV      A, TEMPVAR
MOV      CMNDSTORE, A
 
CHECK_VALID_ADDR:                                                                    ;CHECKING FOR VALID ADDRESS OF REMOTE
 
CJNE     ADDRSTORE, #0CCH, ORIGIN
 
 
ACTIONS:
 
CMD1:                  CJNE CMNDSTORE, #0F7H, CMD2                ;VOLUME DECREASE
MOV A, VOL
CLR C
RRC A
CJNE A, #00H, CON1
SJMP EXIT
CON1:                   MOV VOL, A
SJMP EXIT
 
CMD2:                  CJNE CMNDSTORE, #0E7H, CMD3                ;VOLUME INCREASE
MOV A, VOL
SETB C
RLC A
CJNE A, #0FFH, CON2
SJMP EXIT
CON2:                   MOV VOL, A
SJMP EXIT
 
CMD3:                  CJNE CMNDSTORE, #0F4H, CMD4                ;TREBLE INCREASE
MOV A, TREBLE
CLR C
RLC A
CJNE A, #80H, CON3
SJMP EXIT
CON3:                   MOV TREBLE, A
SJMP EXIT
 
CMD4:                  CJNE CMNDSTORE, #0F2H, CMD5                ;BASS DECREASE
MOV A, BASS
CLR C
RRC A
CJNE A, #01H, CON4
SJMP EXIT
CON4:                   MOV BASS, A
SJMP EXIT
 
CMD5:                  CJNE CMNDSTORE, #0E2H, CMD6                ;BASS INCREASE
MOV A, BASS
CLR C
RLC A
CJNE A, #80H, CON5
SJMP EXIT
CON5:                   MOV BASS, A
SJMP EXIT
 
CMD6:                  CJNE CMNDSTORE, #0E1H, CMD7               ;MUTE
JB 00H, MUTEOFF
MUTEON:            MOV VOLSTORE, VOL
MOV VOL, #00H
SETB 00H
SJMP EXIT
MUTEOFF:          MOV VOL, VOLSTORE
CLR 00H
SJMP EXIT
 
CMD7:                  CJNE CMNDSTORE, #0E7H, EXIT    ;TREBLE DECREASE
MOV A, TREBLE
CLR C
RRC A
CJNE A, #01H, CON7
SJMP EXIT
CON7:                   MOV TREBLE, A
SJMP EXIT
 
EXIT:      LJMP ORIGIN
 
 
FIVESIX:                                                                               ;SUBROUTINE FOR 0.55 MILLISECOND DELAY
MOV      R7, #255
DJNZ     R7, $
MOV      R7, #24
DJNZ     R7, $
RET
 
NINE:
MOV      R5, #16                                 ;SUBROUTINE FOR 9 MILLISECOND DELAY
NINAG: MOV R6, #250
DJNZ     R6, $
DJNZ     R5, NINAG
RET
 
END
 
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Circuit Diagrams



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