Problem in Tension/compression

[Darrel Taylor]

precision,

Give this a try.

DEFINE OSC 20
INCLUDE "MODEDEFS.BAS"
INCLUDE "MYLCD.BAS"

ANSEL = 0 'SELECT ANALOG INPUTS 0 = NONE AND ALL DIGITAL
ADCON0 = 0 'AD MODULE OFF & CONSUMES NO CURRENT
CMCON = 7 'COMPARATORS OFF

TRISA = %00000
TRISB = %00000011  ' INT0 = ENCODER CH. A
                   ' PORTB.1 = ENCODER CH. B
W0     VAR WORD
LastW0 VAR WORD
B1     var word
W0 = 0 
B1 = 0

PAUSE 500                           
'-------------------------------------------------------------------------
INCLUDE "DT_INTS-14.bas"     ; Base Interrupt System
INCLUDE "ReEnterPBP.bas"     ; Include if using PBP interrupts

ASM
INT_LIST  macro    ; IntSource,        Label,  Type, ResetFlag?
        INT_Handler    INT_INT,  _ToggleLED1,   PBP,  yes
    endm
    INT_CREATE               ; Creates the interrupt processor
ENDASM

OPTION_REG.6 = 0   ; 1 = Interrupt on rising edge of INT pin
                   ; 0 = Interrupt on falling edge of INT pin
                                      
@   INT_ENABLE   INT_INT     ; enable external (INT) interrupts

'-------------------------------------------------------------------------
LCDOUT $FE,1

LOOP:   
        IF W0 <> LastW0 then
            LastW0 = W0
                 ' (Peak-Hold), Hold the last value of W0 in B1
            if ABS(LastW0) > ABS(B1) then B1 = LastW0

            LCDOUT $FE,2
            LCDOUT "Length = ", Sdec LastW0, " mm    "
            lcdout $FE, $C0
            lcdout "Peak- Value ",Sdec B1, " mm    "
        ENDIF
GOTO LOOP
         
ToggleLED1:                                    
        if PORTB.1 = 0 then
            W0 = W0+1
        else 
            w0 = w0-1 
        ENDIF
@ INT_RETURN

The range will be +/-32767.

Added: Modified slightly to eliminate changes while displaying.

Modified again to simplify. ABS() works for both pos and neg numbers. Doh!
It also fixes a problem if it moves slightly negative before going positive.
I'll get it right one of these times
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