Hey Guys,
My partner and I are making an audio controller using the PIC16f887. We are trying to get the keyboard we constructed to work like an actual keyboard.
The problem we are running into is the tones coming out of the device (picture attached is a test circuit, programming is also included below). The lowest frequency we can put out is 645.5Hz and for some odd reason 0xFF is as low as we can go since we are using hex for the values (indicated in bold font). The lower the hex value we make it, the higher the frequency outputted.
Anything we can potentially do to try and get it below that 645 so we can get the remaining keys?
NOTE 1: This is only the main program that I am including. We have three macro programs designated for the beep, buttons and pause segments of the program which assist the main program.
NOTE 2 : BEEP HEX1, HEX2;
where HEX1: tone; higher the hex value, the lower the frequency. Maxxed at 0xFF.
where HEX2: length; higher the hex value the longer the tone. Maxxed at 0xFF.
This is the current programming we have:
My partner and I are making an audio controller using the PIC16f887. We are trying to get the keyboard we constructed to work like an actual keyboard.
The problem we are running into is the tones coming out of the device (picture attached is a test circuit, programming is also included below). The lowest frequency we can put out is 645.5Hz and for some odd reason 0xFF is as low as we can go since we are using hex for the values (indicated in bold font). The lower the hex value we make it, the higher the frequency outputted.
Anything we can potentially do to try and get it below that 645 so we can get the remaining keys?
NOTE 1: This is only the main program that I am including. We have three macro programs designated for the beep, buttons and pause segments of the program which assist the main program.
NOTE 2 : BEEP HEX1, HEX2;
where HEX1: tone; higher the hex value, the lower the frequency. Maxxed at 0xFF.
where HEX2: length; higher the hex value the longer the tone. Maxxed at 0xFF.
This is the current programming we have:
Rich (BB code):
;***************************************************************************************
__CONFIG _CONFIG1, _HS_OSC & _WDT_OFF & _PWRTE_ON & _MCLRE_ON & _CP_OFF & _CPD_OFF & _BOR_ON & _IESO_ON & _FCMEN_ON & _LVP_OFF & _DEBUG_OFF
__CONFIG _CONFIG2, _BOR40V & _WRT_OFF
; __CONFIG directive is used to embed configuration data within the .asm file.
; The labels following the directive are located in the respective .inc file.
; See the respective data sheet for additional information on the configuration word.
;****************************************************************************************
;*********************** Header ***************************************
;******************* Defining variables in program ********************
cblock 0x20
HIcnt ; Auxiliary variables for macro pausems
LOcnt
LOOPcnt
PRESCwait
Beep_TEMP1 ; Belongs to macro "BEEP"
Beep_TEMP2
Beep_TEMP3
endc
#define BEEPport PORTD, 2 ; Speaker pin
#define BEEPtris TRISD, 2
expand
;**********************************************************************
ORG 0x0000 ; RESET vector address
goto main ; Jump to program start (label - main)
;**********************************************************************
; remaining code goes here
include "pause.inc"
include "button.inc"
include "beep.inc"
main
main
banksel ANSEL ; Selects bank containing ANSEL
clrf ANSEL ; All outputs are digital
clrf ANSELH
banksel TRISD
movlw b'11111011' ; PORTA D initialization
movwf TRISD
banksel PORTD
BEEPinit ; Macro "Beep"
Loop
button PORTD,0,0,Play1 ; Push-button 1
button PORTD,1,0,Play2 ; Push-button 2
goto Loop
Play1 ; First tone
BEEP 0xFF, 0xFF
goto Loop
Play2 ; Second tone
BEEP 0xBB, 0xFF
goto Loop
;**********************************************************************
END ; End of programAttachments
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