Picaxe 20X2 Interrpt Despatching

interrupt:
      ; *******************************************
      ; Interrupt despatcher - in priority order...
      ; *******************************************


      ;
      ;     Save variables we need to use at Interrupt time
      ;
      ;     NOTE: PTR is NOT currently saved. It IS currently USED
      ;     Do not use it at non-interrupt state
      ;
      Pushram                                         ;;;save W0 - W7
      Push bptr                                       ;;;save bptr (on a different stack)
      ;
      ; Despatch to correct handler
      ;
Despatcher:
      If hint1flag = 1 Then Goto Switch_Pressed       ;;;user interaction is most important
      If hserflag = 1  Then Goto Serial_In            ;;;web server comms.
      If hint2flag = 1 Then Goto HC12                 ;;;inbound temperature reading
      If toflag = 1    Then Goto Timer_Overflow       ;;;time to toggle the LCD display
      Goto DISMISS                                    ;;;unknown interrupt - dismiss
      


Serial_In:
;;;   **********************************************************
;;;   Interrupt handler for Serial In - i.e. data from webserver
;;;   **********************************************************
      #Include "ISR Serial_In.basinc"
      Goto Dismiss                                    ;;;END-OF-INTERRUPT



Timer_Overflow:
;;;   **********************************
;;;   Interrupt handler for Timer Expiry
;;;   **********************************
      #Include "ISR Timer_Overflow.basinc"
      Goto Dismiss                                    ;;;END-OF-INTERRUPT                      
      
Switch_Pressed:
;;;   ****************************************
;;;   Interrupt handler for main switch press.
;;;   ****************************************
      #Include "ISR Switch_Pressed.basinc"
      Goto Dismiss                                    ;;;END-OF-INTERRUPT


HC12:
;     **********************************************************************
;     Interrupt handler for HC-12 458MHz Radio module receiving a character.
;     **********************************************************************
      #Include "ISR HC12.basinc"
      ;Goto Dismiss                                   ;;;END-OF-INTERRUPT (Fall-through)


;;;   *************************************************************************
;;;   END OF INTERRUPT - COMMON EXIT. Also used to initially set up interrupts.
;;;   *************************************************************************
Dismiss:                                              ;;;KEEP
Reset_Interrupts:                                     ;;;TOGETHER
;;;
;;; Each ISR tidies after itself. But what if another Interrupt has occurred while we were processing?
;;; Rather than restoring all the context, re-setting the interrupts, returning and immediately getting called again,
;;; let's check *now* for any other interrupts that need servicing.
;;;            
      If hint1flag = 1 or hserflag = 1 or hint2flag = 1 or toflag = 1  Then Goto Despatcher
      ;b0 = hint1flag + hserflag + hint2flag + toflag
      ;if b0 <> 0 then goto Despatcher                ;;;fancy 'efficient' code is actually 5 bytes longer ;-)


;HC-05 replacement by HC-12 change - Falling edge of "STATE" (Actually a START bit of a received serial byte)
      Hintsetup %00000110                             ;;;set hINT1 (B.0) (switch) to trigger Interrupt at falling edge
                                                      ;;;set hINT2 (B.1) (HC-12) to trigger on falling edge


            ;Bit 7 - reserved
            ;Bit 6 - Interrupt 2 Trigger (1 = rising edge, 0 = falling edge)
            ;Bit 5 - Interrupt 1 Trigger (1 = rising edge, 0 = falling edge)
            ;Bit 4 - Interrupt 0 Trigger (1 = rising edge, 0 = falling edge)
            ;Bit 3 - reserved
            ;Bit 2 - Interrupt 2 Enable
            ;Bit 1 - Interrupt 1 Enable
            ;Bit 0 - Interrupt 0 Enable (not 20X2)


                                                      ;;;set interrupt on Timer overflow OR Hint1 (switch) OR Hint2 (HC-12) or serial char from webserver.
      Setintflags Or %10100110,%10100110              ;;;The condition is the flag ... not the actual hardware condition.
                                                      ;;;The flag is set to "1", by the pin going LOW (makes sense ... ;-)


            ;Bit 7 toflag Timer overflow flag see settimer
            ;Bit 6 hi2cflag hi2c write has occurred (slave mode) see hi2csetup
            ;Bit 5 hserflag hserial backgrounmd receive (see hsersetup)
            ;Bit 4 compflag (see compsetup)
            ;Bit 3 hintflag INT0 or INT1 or INT2
            ;Bit 2 hint2flag INT2 see hintsetup
            ;Bit 1 hint1flag INT1 see hintsetup
            ;Bit 0 hint0flag INT0 (not on this processor)
     
      Pop bptr                                        ;;;restore
      Popram                                          ;;;saved locations
      return                                          ;;;END-OF-INTERRUPT