Skip to navigation

⌂ ∞ ▽ Elite on the BBC Micro and NES

Tactics: SFRMIS

[NES version, Bank 0]

       Name: SFRMIS                                                  [Show more]
       Type: Subroutine
   Category: Tactics
    Summary: Add an enemy missile to our local bubble of universe

    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * TACTICS (Part 5 of 7) calls SFRMIS




 An enemy has fired a missile, so add the missile to our universe if there is
 room, and if there is, make the appropriate warnings and noises.



.SFRMIS

 LDX #MSL               ; Set X to the ship type of a missile, and call SFS1-2
 JSR SFS1-2             ; to add the missile to our universe with an AI flag
                        ; of %11111110 (AI enabled, hostile, no E.C.M.)

 BCC sfrm1              ; The C flag will be set if the call to SFS1-2 was a
                        ; success, so if it's clear, jump to sfrm1 to return
                        ; from the subroutine

 LDA #120               ; Print recursive token 120 ("INCOMING MISSILE") as an
 JSR MESS               ; in-flight message

 LDY #9                 ; Call the NOISE routine with Y = 9 to make the sound
 JMP NOISE              ; of the missile being launched and return from the
                        ; subroutine using a tail call

.sfrm1

 RTS                    ; Return from the subroutine