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⌂ ∞ Elite on the BBC Micro and NES

Universe: KS4

[Acorn Electron version]

       Name: KS4                                                     [Show more]
       Type: Subroutine
   Category: Universe
    Summary: Remove the space station and replace with a placeholder

    Context: See this subroutine in context in the source code
 Variations: See code variations for this subroutine in the different versions
 References: This subroutine is called as follows:
             * KILLSHP calls KS4




.KS4

 JSR ZINF               \ Call ZINF to reset the INWK ship workspace

 LDA #0                 \ Set A = 0 so we can zero the following flags

 STA FRIN+1             \ Set the second slot in the FRIN table to 0, which
                        \ sets this slot to empty, so when we call NWSHP below
                        \ the placeholder that gets created will go into FRIN+1

 STA SSPR               \ Set the "space station present" flag to 0, as we are
                        \ no longer in the space station's safe zone

 JSR SPBLB              \ Call SPBLB to redraw the space station bulb, which
                        \ will erase it from the dashboard

 LDA #6                 \ Set the placeholder's y_sign to 6
 STA INWK+5

 LDA #129               \ Set A = 129, the ship type for the placeholder, so
                        \ there isn't a space station, but there is a non-zero
                        \ ship type to indicate this

 JMP NWSHP              \ Call NWSHP to set up the new data block and add it
                        \ to FRIN, where it will get put in the second slot as
                        \ we just cleared out the second slot, and the first
                        \ slot is already taken by the planet