Flight model: RetractFlapsIfFast

       Name: RetractFlapsIfFast                                      [Show more]
       Type: Subroutine
   Category: Flight model
    Summary: Retract the flaps if we are going faster than 150 mph
    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * ApplyTurnAndThrust (Part 2 of 2) calls RetractFlapsIfFast


 Arguments:

   A                    The high byte of the current airspeed


.RetractFlapsIfFast

 CMP #14                \ First we check the high byte of the current airspeed
 BCC flap1              \ in A to see if it is less than 14, at which point the
                        \ airspeed is:
                        \
                        \   (14 0) * 100 / 2368 = 3584 * 100 / 2368 = 151
                        \
                        \ So if the airspeed is less than 151mph, we jump to
                        \ flap1 to return from the subroutine without changing
                        \ the flaps

 LDA flapsStatus        \ If the flaps are already retracted, jump to flap1 to
 BEQ flap1              \ return from the subroutine without changing anything

 LDA #0                 \ The speed is at least 151 mph and the flaps are on,
 STA flapsStatus        \ so we retract them by setting flapsStatus to 0

 JSR IndicatorF         \ Update the flaps indicator

.flap1

 RTS                    \ Return from the subroutine