5x7 Display Piezo Experiments Page2

EXPERIMENT-5P   CALLing  Hee Haw  routine
This experiment shows how to CALL Hee Haw routine when a certain event has occurred. In this case the program detects button B.       Hee Haw repeats 5 times then stops. 

Experiment-5P for "Piezo on 5x7 Display" Project                                ;PIC16F84 and only F84 chip                                            ;Calling Hee Haw Siren    Start       ORG 0x00                BSF 03,5                 ;Go to page1 to set up the ports                 MOVLW 08h           ;Load W with 0000 1000                MOVWF 05h           ; to make RA3 input                 MOVLW 00h           ;Put 00 into W                 MOVWF 06h           ;to make all RB lines output                BCF 03,5                 ;Go to Page0 for programming                GOTO Main                           ;Hee - this is the LOW frequency   Hee       MOVLW 0FFh                 MOVWF 06            ;Turn ON all LEDs                MOVLW 04                 MOVWF 1C  Hee1      MOVLW 080h                MOVWF 1B  Hee2      MOVLW 80h          ;Toggle the piezo line.                 XORWF 06h,1                MOVLW 0B0h                MOVWF 1Ah                CALL Delay           ;Call Delay                 DECFSZ 1B,1                GOTO Hee2           ;Repeat the routine as per file 1B                 DECFSZ 1C,1                 GOTO Hee1                      ;Haw - This is the HIGH frequency  Haw       MOVLW 00                MOVWF 06           ;Turn OFF all LEDs                MOVLW 04                 MOVWF 1C  Haw1    MOVLW 0D0h         ;Create D0 loops                MOVWF 1B  Haw2    MOVLW 80h          ;Toggle the piezo line.                 XORWF 06h,1                 MOVLW 80h                MOVWF 1Ah                CALL Delay           ;Call Delay                 DECFSZ 1B,1                GOTO Haw2         ;Repeat the routine as per file 1B                DECFSZ 1C,1                 GOTO Haw1                RETURN  Delay     DECFSZ 1Ah,1      ;Length of ON and OFF time for tone                GOTO Delay                 RETURN  Main       BTFSS 05,3          ;Is button B pressed?                GOTO Main          ;No                MOVLW 05          ;Yes. Create 5 loops for Hee Haw                MOVWF 1Dh   Main1    CALL Hee                DECFSZ 1Dh,1                GOTO Main1  Main2    CALL Delay                BTFSC 05,3               ;Is button B released?                GOTO Main2              ;No                GOTO Main               ;Yes button B is released!                END

	The block of numbers below is the HEX file for Experiment-5P. Copy and paste it into a text program such as TEXTPAD or NOTEPAD and call it: Expt5P.hex
	:100000008316083085000030860083122928FF30CF :10001000860004309C0080309B0080308606B03023 :100020009A0026209B0B0D289C0B0B280030860085 :1000300004309C00D0309B008030860680309A00CF :1000400026209B0B1C289C0B1A2808009A0B26289C :100050000800851D292805309D0007209D0B2D28AF :0800600026208519302829280B :00000001FF

 
EXPERIMENT-6P   Making a Note
Making a Note is slightly different to making a tone. A note has to be very close in frequency to the correct value so it will be recognised. 
The first step in making a tune is the creation of the notes and in this experiment we show how to make a note. 
Each note is made up of an ON time (the HIGH for the note) and an OFF time (the LOW for the note). This must then be repeated to produce the note.
The sub-routine "C" produces both the HIGH and LOW times by toggling the line connected to the piezo then calling the delay. This action is repeated endlessly to create the note. 
The delay has been specially designed to take exactly 8 "units of time" (one unit of time for each NOP and DECFSZ and two units for GOTO. File 1A is loaded with F0 (240) and this creates 240 x 8 = 1920 microseconds of delay. The "C" sub-routine takes 8 microseconds (CALL = 2 microseconds) and GOTO takes 2 microseconds of time. The last cycle of delay takes 9 microseconds. 
When this is all added up, the result is 1929 microseconds. The other half of the cycle takes the same length of time and when 1,000,000 is divided by (1929x2), the result is very close to 260Hz. 
Middle C is specified as 261.63Hz and you cannot get much closer. 
The diagram below shows one cycle of tone "C" with       HIGH = 1929 microseconds and   LOW = 1929 microseconds. 

 

Experiment-6P for Piezo on "5x7 Display" Project                                       ;PIC16F84 and only F84 chip                                        ;Making a Note - middle "C"  Start      ORG 0x00                BSF 03,5           ;Go to page1 to set up the ports                 MOVLW 00h     ;Put 00 into W                 MOVWF 05h     ;Make all RA lines output                 MOVWF 06h     ;Make all RB lines output                BCF 03,5           ;Go to Page0 for programming                                     ;Producing "middle C"  C            MOVLW 80h      ;Toggle the piezo line.                 XORWF 06h,1                MOVLW 0F0h                MOVWF 1Ah                CALL Delay        ;Call Delay                 GOTO C              ;Repeat the routine   Delay     NOP                    ;Length of ON and OFF time for Note                 NOP                NOP                NOP                NOP                DECFSZ 1Ah,1                GOTO Delay                 RETURN                END

	The block of numbers below is the HEX file for Experiment-6P. Copy and paste it into a text program such as TEXTPAD or NOTEPAD and call it: Expt6P.hex
	:1000000083160030850086008312803086067630A5 :100010009A000B20052800000000000000000000EE :060020009A0B0B280800FA :00000001FF

 
EXPERIMENT-7P   Creating a Scale
The natural extension of note-making is to create a tune. But first we need to create the 8 notes in the octave from middle C to upper C. These will then be placed in a routine and looped. 
One feature that may go un-noticed is the length of each note. As the note increases in frequency, the number of cycles has to be increased so that the length of the note is the same as the others. That's why each note must have two variables - the duration of the HIGH/ LOW and the number of cycles. The advantage of knowing the time taken to execute each instruction means you can work out the time taken for each sub-routine and thus get the frequency of each note accurate without having to measure it with a Frequency Counter. We checked the frequency of each note and found it to be only about 2 cycles from the accepted value. 
We used a 4MHz crystal when writing this experiment and the notes will alter if the RC components on the PC board do not create a 4MHz oscillator. 
If you want a much cleaner and clearer output from the project, use a mini speaker in place of the piezo. 

Experiment-7P for Piezo on "5x7 Display" Project                                       ;PIC16F84 and only F84 chip                                         ;Creating a SCALE  Start       ORG 0x00                BSF 03,5          ;Go to page1 to set up the ports                 MOVLW 00h    ;Put 00 into W                 MOVWF 05h    ;Make all RA lines output                 MOVWF 06h    ;Make all RB lines output                BCF 03,5          ;Go to Page0 for programming                GOTO Main  Note       MOVLW 80h    ;Toggle the piezo line.                 XORWF 06h,1                 MOVF 1A,0      ;Copy file 1A into W                MOVWF 1Ch    ;Move W into file 1C                CALL Delay      ;Call Delay                 DECFSZ 1Bh,1 ;Dec file 1B for length of note                GOTO Note                RETURN   Delay     NOP                ;Length of ON and OFF time for Note                 NOP                NOP                NOP                NOP                DECFSZ 1Ch,1                GOTO Delay                 RETURN  Main       MOVLW 0F0h      ;Frequency of note C - 261Hz                MOVWF 1Ah                MOVLW 80h        ;Length of note C                MOVWF 1Bh                CALL Note                MOVLW 0D5h      ;Frequency of note D - 293Hz                MOVWF 1Ah                MOVLW 90h         ;Length of note D                MOVWF 1Bh                CALL Note                MOVLW 0BDh       ;Frequency of note E - 330Hz                MOVWF 1Ah                MOVLW 0A0h       ;Length of note E                MOVWF 1Bh                CALL Note                MOVLW 0B2h        ;Frequency of note F - 349Hz                MOVWF 1Ah                MOVLW 0B0h        ;Length of note F                MOVWF 1Bh                CALL Note                MOVLW 09Fh         ;Frequency of note G - 392Hz                MOVWF 1Ah                MOVLW 0C0h         ;Length of note G                MOVWF 1Bh                CALL Note                MOVLW 08Dh         ;Frequency of note A - 440Hz                MOVWF 1Ah                MOVLW 0D0h         ;Length of note A                MOVWF 1Bh                CALL Note                MOVLW 07Eh          ;Frequency of note B - 494Hz                MOVWF 1Ah                MOVLW 0E0h          ;Length of note B                MOVWF 1Bh                CALL Note                MOVLW 077h          ;Frequency of note C' - 523Hz                MOVWF 1Ah                MOVLW 0F0h          ;Length of note C'                MOVWF 1Bh                CALL Note                GOTO Main                 END

	The block of numbers below is the HEX file for Experiment-7P. Copy and paste it into a text program such as TEXTPAD or NOTEPAD and call it: Expt7P.hex
	:10000000831600308500860083121628803086060D :100010001A089C000E209B0B062808000000000018 :100020000000000000009C0B0E280800F0309A0031 :1000300080309B000620D5309A0090309B0006202F :10004000BD309A00A0309B000620B2309A00B0303C :100050009B0006209F309A00C0309B0006208D3008 :100060009A00D0309B0006207E309A00E0309B0042 :0E007000062077309A00F0309B0006201628FC :00000001FF

 
EXPERIMENT-8P   Creating a tune 
This experiment shows how to set up sub-routines for each note so they can be CALLed by using a single instruction. 

Experiment-8P for Piezo on "5x7 Display" Project                                       ;PIC16F84                                        ;Creating a TUNE                                       ;Oh,  When The Saints  Start      ORG 0x00               BSF 03,5              ;Go to page1 to set up the ports                MOVLW 00h        ;Put 00 into W                MOVWF 05h        ;Make all RA lines output                MOVWF 06h        ;Make all RB lines output               BCF 03,5              ;Go to Page0 for programming               GOTO Main  C           MOVLW 80h               MOVWF 1Bh   NoteC    MOVLW 80h          ;Toggle the piezo line.                XORWF 06h,1                MOVLW 0F0h               MOVWF 1Ah                CALL Delay            ;Call Delay                DECFSZ 1Bh,1        ;Dec file 1B for length of note               GOTO NoteC               RETURN   D           MOVLW 90h               MOVWF 1Bh   NoteD   MOVLW 80h           ;Toggle the piezo line.                XORWF 06h,1                MOVLW 0D5h               MOVWF 1Ah                CALL Delay              ;Call Delay                DECFSZ 1Bh,1         ;Dec file 1B for length of note               GOTO NoteD               RETURN   E           MOVLW 0A0h               MOVWF 1Bh   NoteE    MOVLW 80h            ;Toggle the piezo line.                XORWF 06h,1                MOVLW 0BDh               MOVWF 1Ah                CALL Delay              ;Call Delay                DECFSZ 1Bh,1         ;Dec file 1B for length of note               GOTO NoteE               RETURN   F           MOVLW 0B0h               MOVWF 1Bh   NoteF    MOVLW 80h             ;Toggle the piezo line.                XORWF 06h,1                MOVLW 0B2h               MOVWF 1Ah                CALL Delay               ;Call Delay                DECFSZ 1Bh,1          ;Dec file 1B for length of note               GOTO NoteF               RETURN   G          MOVLW 0C0h               MOVWF 1Bh   NoteG   MOVLW 80h               ;Toggle the piezo line.                XORWF 06h,1                MOVLW 9Fh               MOVWF 1Ah                CALL Delay                ;Call Delay                DECFSZ 1Bh,1           ;Dec file 1B for length of note               GOTO NoteG               RETURN   A          MOVLW 0D0h               MOVWF 1Bh   NoteA   MOVLW 80h               ;Toggle the piezo line.                XORWF 06h,1                MOVLW 8Dh               MOVWF 1Ah                CALL Delay                   ;Call Delay                DECFSZ 1Bh,1              ;Dec file 1B for length of note               GOTO NoteA               RETURN   BB        MOVLW 0E0h               MOVWF 1Bh   NoteB    MOVLW 80h                     ;Toggle the piezo line.                 XORWF 06h,1                MOVLW 7Eh               MOVWF 1Ah                CALL Delay                       ;Call Delay                DECFSZ 1Bh,1                  ;Dec file 1B for length of note               GOTO NoteB               RETURN   CC        MOVLW 0F0h               MOVWF 1Bh   NoteCC MOVLW 80h                  ;Toggle the piezo line.                 XORWF 06h,1                MOVLW 77h               MOVWF 1Ah                CALL Delay                     ;Call Delay                DECFSZ 1Bh,1                ;Dec file 1B for length of note               GOTO NoteCC               RETURN  Delay      NOP               ;Length of ON and OFF time for Note                NOP               NOP               NOP               NOP               DECFSZ 1Ah,1               GOTO Delay                RETURN                                                     ;Oh, When the Saints Come Marching in: Main       CALL C               CALL E               CALL F               CALL G               CALL G               CALL G               CALL G               CALL G               CALL C               CALL E               CALL F               CALL G               CALL G               CALL G               CALL G               CALL G               CALL C               CALL E               CALL F               CALL G               CALL G               CALL E               CALL E               CALL C               CALL C               CALL E               CALL E               CALL D               CALL D               CALL D               CALL D               CALL D               CALL Delay               CALL Delay               CALL E               CALL D               CALL C               CALL C               CALL Delay               CALL C               CALL C               CALL E               CALL E               CALL G               CALL G               CALL G               CALL F               CALL F               CALL F               CALL F               CALL F               CALL E               CALL F               CALL G               CALL G               CALL E               CALL E               CALL D               CALL D               CALL Delay               CALL D               CALL D               CALL C               CALL C               CALL C               CALL Delay               CALL C               GOTO Main               END

The block of numbers below is the HEX file for Experiment-8P. Copy and paste it into a text program such as TEXTPAD or NOTEPAD and call it: Expt8P.hex

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

You now have the option of going over the experiments again or starting to write your own programs. 
To produce your own programs you will need a program called MPASM. This will assemble the programs you write on Notepad and create a .hex file (as well as other files). 
Before you start writing programs, go to PIC Theory.