Dashboard: UpdateFuelGauge

       Name: UpdateFuelGauge                                         [Show more]
       Type: Subroutine
   Category: Dashboard
    Summary: Update the fuel gauge every 16 iterations of the main loop
  Deep dive: Scheduling tasks in the main loop
    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * MainLoop (Part 11 of 15) calls UpdateFuelGauge
             * ResetVariables calls UpdateFuelGauge


.UpdateFuelGauge

 LDA mainLoopCounter    \ If the mainLoopCounter is a multiple of 16, jump to
 AND #15                \ upfu1 to update the fuel gauge
 BEQ upfu1

 RTS                    \ Return from the subroutine

.upfu1

 LDX #128               \ Set X = 128, so we erase a pixel from the top of the
                        \ fuel gauge in DrawFuelPixel below, if there is one

 LDA fuelLevel          \ Set A = fuelLevel

                        \ Fall through into DrawFuelPixel to erase a pixel from
                        \ the fuel gauge at the top of the gauge if there is
                        \ one, which will set the amount shown on the fuel gauge
                        \ to fuelLevel