Dashboard: MSBAR

       Name: MSBAR                                                   [Show more]
       Type: Subroutine
   Category: Dashboard
    Summary: Draw a specific indicator in the dashboard's missile bar
    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * ABORT2 calls MSBAR
             * Main flight loop (Part 3 of 16) calls MSBAR
             * msblob calls MSBAR


 Arguments:

   X                    The number of the missile indicator to update (counting
                        from bottom-right to bottom-left, then top-left and
                        top-right, so indicator NOMSL is the top-right
                        indicator)

   Y                    The pattern number for the new missile indicator:

                          * 133 = no missile indicator

                          * 109 = red (armed and locked)

                          * 108 = black (disarmed)

                        The armed missile flashes black and red, so the tile is
                        swapped between 108 and 109 in the main loop


 Returns:

   X                    X is preserved

   Y                    Y is set to 0


.MSBAR

 TYA                    ; Store the pattern number on the stack so we can
 PHA                    ; retrieve it later

 LDY missileNames,X     ; Set Y to the X-th entry from the missileNames table,
                        ; so Y is the offset of missile X's indicator in the
                        ; nametable buffer, from the start of row 22

 PLA                    ; Set the nametable buffer entry to the pattern number
 STA nameBuffer0+22*32,Y

 LDY #0                 ; Set Y = 0 to return from the subroutine (so this
                        ; routine behaves like the same routine in the other
                        ; versions of Elite)

 RTS                    ; Return from the subroutine