newbe wants to store in 16f887 eeprom help

I am using a DTMF decoder with the 16f887 chip. The decoder circuit works great which and simply runs a program, and that works great. is there a statement that can tell the e prom in the 16f887 chip to run a goto routine r something like that. I want the e prom to hold this in memory forever and always run this new routine. then upon another DTMF command, it will go back to the normal routine that it started with. The DTMF part of this is solved. But cannot figure the e prom storage part of it. Thanks Leon

What about GOSUB the special routine IF you get that DTMF command, ELSE GOSUB the regular routine?

You can add more routines in the IF later for extra DTMF commands.

Robert

I suspect you need SELECT CASE in the program not the eprom space which is used for DATA storage.

I'm guessing you are using the tones as a control method. So you want a single tone or combination of tones to do something.

You need to save the output of the tone decoder to a variable then use the variable result to Select Case . Each CASE can have the code you want to run.

It's in the PBP manual.

Eeprom is useful if your device powers down and up and you want continuity in your logic.

Store your variable to eeprom before shutting down,then read it after power up and return it in a variable.

Robert

Hi Demon, sounds like you are smart. What you are explaining makes sense. Yes, the DTMF decoder output goes to 4 ports of the 16f877. It is easy to do, If portx and portx and portx and portx=1 then decode or something like that. I do have the DTMF decoder and chip to work great. But I am trying to learn how to write the basic code to get the eprom to store this and turn on a port that will always
upon 16f887 power up (once activated)will always turn on this port until a different(reset) DTMF code is received. Once the reset DTMF code is received, this port will not turn on up power up. I have tried with no success to get this to work. Any help on code to do this. Point me in the right direction. Thanks so much, Leon

I know I'm not smart enough but here's a small program i wrote to generate frequencies.

Note that it reads and stores values both previous and new values to eeprom.

Code:

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'****************************************************************
'*  Name    : freqgen.BAS                                      *
'*  Author  : Rob Lane                                          *
'*  Notice  : Copyright (c) 2011                                *
'*          : All Rights Reserved                              *
'*  Date    : 09/08/2011                                        *
'*  Version : 1.0                                              *
'*  Notes  :                                                  *
'*          :                                                  *
'****************************************************************

    eeprom 4,[$10,$0e]  ' program in first run freq value 3600Hz (lowest)
   
    include "Modedefs.bas"      ' for lcd baud rate
   
    define OSC 10              ' for lcd baud rate 9600


Duty        var byte        'duty cycle value (max 255)
Freqval    var word        'frequency variable
A2          var byte        'Button' variable
Counter1    var byte
PercVal    var word
PercVal2    Var byte
        '      Control Buttons/Lines
        '      ----------------------

    TRISA=%00011111      ' button pins
    TRISB=%00000000      ' port b as outputs
 
    CMCON=7              ' comparator ports to digital
   
    Pause 500 ' lcd to settle
   
    read 4,Freqval.byte0    'read previously stored freq
    read 5,Freqval.byte1    'from eeprom at power up
    SERout PortB.7,N9600,[254,1]  'lcd CLS
    pause 10                ' needed after cls command
    Duty=64                ' set HPWM duty cycle
    A2=0                    ' set button debounce
    hpwm 1,Duty,Freqval        'output freq to hardware pwm channel 1
    PercVal=(Duty*1000)/256
    PercVal2=PercVal dig 0
    PercVal=(Duty*100)/256
   
mainloop:
    serout PortB.7,N9600,[254,128]  'lcd line 1 home
    SERout PortB.7,N9600,["Frequency: ",#Freqval ]
    serout PortB.7,N9600,[254,192]  'lcd line 1 home
    SERout PortB.7,N9600,["Duty cycle: ",#PercVal ,".",#PercVal2,"%" ]
    Button PortA.0,0,255,0,A2,1,upfaster   
    Button PortA.1,0,255,0,A2,1,downfaster
    Button PortA.3,0,255,0,A2,1,upslow
    Button PortA.4,0,255,0,A2,1,downslow
    high PortB.0      '==  LED on
    pause 500          '==  blink led to show in loop
    low PortB.0        '==  LED off
    pause 500          '==  for testing purposes
    goto mainloop         
 
   
freqgenoff:
    TRISB=%00001000    'turn off hpwm register
    goto mainloop
   
freqsave:
    write 4,Freqval.byte0  'save freq to eeprom
    write 5,Freqval.byte1  'at button press end and
    goto mainloop          'return to main loop 
   
'UP FAST ===============================   
upfaster:
    read 4,Freqval.byte0
    read 5,Freqval.byte1   
     
upfast:
    if PortA.0=1 then freqsave  ' 1st trap exit to 'save' loop
    hpwm 1,Duty,Freqval        'output freq to hardware pwm channel 1
    serout PortB.7,N9600,[254,128]
    SERout PortB.7,N9600,["Frequency: ",#Freqval ]
    Freqval=Freqval+100      'increment freq
    if Freqval>=32000 then freqval=32000  'hold if at highest freq figure
    pause 5                          'slows looping
    if PortA.0=1 then freqsave          '2nd trap exit to 'save' loop
    goto upfast
   
 'DOWN FAST ===============================   
downfaster:
    read 4,Freqval.byte0
    read 5,Freqval.byte1   
     
downfast:
    if PortA.1=1 then freqsave  ' 1st trap exit to 'save' loop
    hpwm 1,Duty,Freqval        'output freq to hardware pwm channel 1
    serout PortB.7,N9600,[254,128]
    SERout PortB.7,N9600,["Frequency: ",#Freqval ]
    Freqval=Freqval-100      'decrement freq
    if Freqval<=700 then freqval=700  'hold if at highest freq figure
    pause 5                          'slows looping
    if PortA.1=1 then freqsave          '2nd trap exit to 'save' loop
    goto downfast 
       
   
'UP Routine ============================
 
upslow:
    read 4,Freqval.byte0
    read 5,Freqval.byte1   
    counter1=1
     
slowup:
    For counter1 = 1 to 5      ' if press longer than 5 then speedup
    if PortA.3=1 then freqsave  ' 1st trap exit to 'save' loop
    hpwm 1,Duty,Freqval        'output freq to hardware pwm channel 1
    serout PortB.7,N9600,[254,128]
    SERout PortB.7,N9600,["Frequency: ",#Freqval ]
    Freqval=Freqval+1      'increment freq
    if Freqval>=32000 then freqval=32000  'hold if at highest freq figure
    pause 500                          'slows looping
    if PortA.3=1 then freqsave          '2nd trap exit to 'save' loop
    next counter1
    goto frequp
 
frequp:
    if PortA.3=1 then freqsave  ' 1st trap exit to 'save' loop 
    hpwm 1,Duty,Freqval      'output freq to hardware pwm channel 1 @ 25% duty cycle(64)
    serout PortB.7,N9600,[254,128]
    SERout PortB.7,N9600,["Frequency: ",#Freqval ]
    Freqval=Freqval+10      'increment freq
    if Freqval>=32000 then freqval=32000  'hold if at highest freq figure 
    pause 50                      'slows looping
    if PortA.3=1 then freqsave  '2nd trap exit to 'save' loop or
    if PortA.3=0 then frequp    'loop frequp
   
'DOWN Routine ==========================
   
downslow:   
    read 4,Freqval.byte0
    read 5,Freqval.byte1
    counter1=1
   
slowdown:
    For counter1 = 1 to 5
    if PortA.4=1 then freqsave  ' 1st trap exit to 'save' loop
    hpwm 1,Duty,Freqval      'output freq to hardware pwm channel 1 @ 25% duty cycle(64)
    serout PortB.7,N9600,[254,128]
    SERout PortB.7,N9600,["Frequency: ",#Freqval ]
    Freqval=Freqval-1      'decrement freq
    if Freqval<=700 then freqval=700  'hold if at lowest freq figure
    pause 500                          'slows looping
    if PortA.4=1 then freqsave  '2nd trap exit to 'save' loop             
    next counter1
    goto freqdown
   
freqdown:
    if PortA.4=1 then freqsave     
    hpwm 1,Duty,Freqval
    serout PortB.7,N9600,[254,128]
    SERout PortB.7,N9600,["Frequency: ",#Freqval ]
    Freqval=Freqval-10
    if Freqval<=700 then freqval=700  ' hold if at lowest freq figure
    pause 50
    if PortA.4=1 then freqsave
    if PortA.4=0 then freqdown   
 
end

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