New approach to Rotary Encoder

[fratello]

Step-by-step I think I begin to understand ...
The correct hardware it's this.
The software can be this :

@ DEVICE pic16F628A, XT_OSC, WDT_OFF, PWRT_ON, BOD_OFF, MCLR_ON, LVP_OFF

   Define   OSC 4           ' 4MHz 
   CMCON = 7                ' Disable on-chip comparator, PORTA in digital mode

include "alldigital.pbp"
include "C:\PBP\enc_KEY.BAS" 

TRISB = 000000
PORTB = 000000 

oldState VAR BYTE
newState VAR BYTE
DIR VAR BIT

UP CON 1
DN CON 0

Main_Loop: 
portb.5 = 1
gosub keypadscan
gosub check
goto main_loop

Check :
if dir = up then 
portb.0 = 1
pause 1000
portb.0 = 0
endif
if dir = dn then
portb.1 = 1
pause 1000
portb.1 = 0
endif
return

encoder:
portb.5 = 0
    newState = (porta & 000111)
If newState <> oldState THEN        ' Changed from last time?
  Select Case oldState
    Case 2
    If NewState = 4 THEN          ' Was 1 now 4 = Up
      DIR = up
    ELSE                          ' Was 1 now 2 = Down
      DIR = dn
    ENDIF
  
    Case 4
    If NewState = 1  THEN        ' Was 2 now 1 = Up
      DIR = up
    ELSE                           ' Was 2 now 4 = Down
      DIR = dn
    ENDIF
  
    Case 1
    If NewState = 2 THEN        ' Was 4 now 2 = Up
      DIR = up
    ELSE                       ' Was 4 now 1 = Down
      DIR = dn
    ENDIF
  END SELECT

  oldState = NewState 
endif
portb.5 = 1
Return

The question is : where to put "gosub encoder" ? Inside the "enc_key.bas" (it's keypad.bas addapted to 2 row/3 cols) ???