Hello tenaja,

I tried your suggestion and still no go. Can you or anyone else here think of any other avenues that I could explore to get it working?

Thanks
jessey

Code:
Enter_Access_Code:
 select_dtmf = 1   ' Enable the data output from the MT8870
 Pause 1     ' Pause 1 mS to let data settle
 dtmf_digit = (PORTB >> 4) ' Read the top nibble of PORTB for DTMF data

 ' Use LOOKUP to change the DTMF data to an ASCII character
 LookUp dtmf_digit, ["_1234567890*#ABCD"], dtmf_digit

dtmf_wait2:     
 IF dtmf_ready Then dtmf_wait2 ' Loop here until DTMF signal stops
 select_dtmf = 0   ' Disable the MT8870 data output

' access code is 2457316

 Select Case dtmf_digit       ' Take action based on the dtmf digit

'6th # in the correct sequence --- 1 = A
  Case "1"    ' sets A var to 1 if 1 is pressed and If-Then below is correct..
 'IF (A=0) AND (B=1) AND (C=1) AND (D=1) AND (E=1) AND (F=0) AND (G=1) THEN A=1
  IF (A=0) then
   if (B=1) then
    if (C=1) then
     if (D=1) then
      if (E=1) then
       if (F=0) then
        if (G=1) THEN
  A=1
   endif
    endif
     endif
      endif
       endif
        endif
        ELSE
    A=2 ' 2681
  ENDIF ' 2639
        '   52


'1st # in the correct sequence --- 2 = B
  Case "2"    ' sets B var to 1 if 2 is pressed and If-Then below is correct..
 'IF (A=0) AND (B=0) AND (C=0) AND (D=0) AND (E=0) AND (F=0) AND (G=0) THEN B=1
   IF (A=0) then
    if (B=0) then
     if (C=0) then
      if (D=0) then
       if (E=0) then
        if (F=0) then
         if (G=0) THEN
   B=1
    endif
     endif
      endif
       endif
        endif
         endif
         ELSE
     B=2
   ENDIF

'5th # in the correct sequence --- 3 = C 
  Case "3"    ' sets C var to 1 if 3 is pressed and If-Then below is correct..
  'IF (A=0) AND (B=1) AND (C=0) AND (D=1) AND (E=1) AND (F=0) AND (G=1) THEN C=1
   IF (A=0) then
    if (B=1) then
     if (C=0) then
      if (D=1) then
       if (E=1) then
        if (F=0) then
         if (G=1) THEN
   C=1
    endif
     endif
      endif
       endif
        endif
         endif
         ELSE
     C=2
   ENDIF

'2nd # in the correct sequence --- 4 = D
  Case "4"    ' sets D var to 1 if 4 is pressed and If-Then below is correct..
  'IF (A=0) AND (B=1) AND (C=0) AND (D=0) AND (E=0) AND (F=0) AND (G=0) THEN D=1
   IF (A=0) then
    if (B=1) then
     if (C=0) then
      if (D=0) then
       if (E=0) then
        if (F=0) then
         if (G=0) THEN
   D=1
    endif
     endif
      endif
       endif
        endif
         endif
         ELSE
     D=2
   ENDIF

'3rd # in the correct sequence --- 5 = E
  Case "5"    ' sets E var to 1 if 5 is pressed and If-Then below is correct..
  'IF (A=0) AND (B=1) AND (C=0) AND (D=1) AND (E=0) AND (F=0) AND (G=0) THEN E=1
   IF (A=0) then
    if (B=1) then
     if (C=0) then
      if (D=1) then
       if (E=0) then
        if (F=0) then
         if (G=0) THEN
   E=1
    endif
     endif
      endif
       endif
        endif
         endif
         ELSE
     E=2
   ENDIF

'7th # in the correct sequence --- 6 = F   
  Case "6"    ' sets F var to 1 if 6 is pressed and If-Then below is correct..
  'IF (A=1) AND (B=1) AND (C=1) AND (D=1) AND (E=1) AND (F=0) AND (G=1) THEN F=1
   IF (A=1) then
    if (B=1) then
     if (C=1) then
      if (D=1) then
       if (E=1) then
        if (F=0) then
         if (G=1) THEN
   F=1
    endif
     endif
      endif
       endif
        endif
         endif
         ELSE
     F=2
   ENDIF

'4th # in the correct sequence --- 7 = G   
  Case "7"    ' sets G var to 1 if 6 is pressed and If-Then below is correct..
  'IF (A=0) AND (B=1) AND (C=0) AND (D=1) AND (E=1) AND (F=0) AND (G=0) THEN G=1
   IF (A=0) then
    if (B=1) then
     if (C=0) then
      if (D=1) then
       if (E=1) then
        if (F=0) then
         if (G=0) THEN
   G=1
    endif
     endif
      endif
       endif
        endif
         endif
         ELSE
     G=2
   ENDIF

  Case "8"
    A=2   ' If the #8 key is pressed then it's a no go

  Case "9"
    A=2   ' If the #9 key is pressed then it's a no go

  Case "0"
    A=2   ' If the #0 key is pressed then it's  a no go

 End Select

'IF (A=1) AND (B=1) AND (C=1) AND (D=1) AND (E=1) AND (F=1) AND (G=1) THEN
 IF (A=1) then
  if (B=1) then
   if (C=1) then
    if (D=1) then
     if (E=1) then
      if (F=1) then
       if (G=1) THEN
   access_code = is_verified 
   FreqOut DTMF_out, 500, 800  ' Play 3 tones to confirm to the caller that
   PAUSE 100                   ' the correct access code has been entered
   FreqOut DTMF_out, 500, 800
   PAUSE 100
   FreqOut DTMF_out, 500, 800
  endif
   endif
    endif
     endif
      endif
       endif
 ENDIF
IF k = 0 THEN listen