Elapsed Timer findings

[richard]

did you see this

'***************************************************************************
'*  Name    : Elapsed_INT-18.bas                                           *
'*  Author  : Darrel Taylor                                                *
'*  Date    : JUL 11, 2006 : 7/11/2010                                     *
'*  Version : 1.2                                                          *
'*  Notes   : Must have DT_INTS-18.bas loaded first                        *
'*   ver 1.2: Now works at any OSC frequency without using the prescaler   *
'***************************************************************************

the pic16 ver can work up to and including 32MHz without the need of a prescaler if necessary

'****************************************************************
'*  Name    : Elapsed_INT.bas                                   *
'*  Author  : Darrel Taylor                                     *
'*  Date    : Jan 10, 2006                                      *
'*  Notes   : Must have DT_INTS-??.bas loaded first             *
'****************************************************************
DISABLE DEBUG
; syntax =     Handler  IntSource,        Label, Type, ResetFlag?
DEFINE  Elapsed_Handler  TMR1_INT,  _ClockCount,  PBP,  yes
; the above define can be used in the INT_LIST macro, if desired (optional)


Ticks    var byte   ' 1/100th of a second
Seconds  var byte
Minutes  var byte
Hours    var byte
Days     var word


SecondsChanged   var bit
MinutesChanged   var bit
HoursChanged     var bit
DaysChanged      var bit
SecondsChanged = 1
MinutesChanged = 1


Goto OverElapsed


' ------------------------------------------------------------------------------
' To calculate a constant for a different crystal frequency - see this web page
' http://www.picbasic.co.uk/forum/showthread.php?t=2031
' ------------------------------------------------------------------------------
Asm
  IF OSC == 4                       ; Constants for 100hz interrupt from Timer1
TimerConst = 0D8F7h                 ; Executed at compile time only
  EndIF
  If OSC == 8
TimerConst = 0B1E7h
  EndIF
  If OSC == 10
TimerConst = 09E5Fh
  EndIF
  If OSC == 16
TimerConst = 063C7h
  EndIF
  If OSC == 20
TimerConst = 03CB7h
  EndIF
  If OSC == 32
TimerConst = 25539
  EndIF