Version analysis of ABORT - Elite on the 6502

This code appears in the following versions (click to see it in the source code):

Cassette, Disc (flight), Disc (docked), 6502 Second Processor, Master and Electron

Code variations between these versions are shown below.

       Name: ABORT
       Type: Subroutine
   Category: Dashboard
    Summary: Disarm missiles and update the dashboard indicators


 Arguments:

   Y                    The new status of the leftmost missile indicator

Code variation 1 of 2A variation in the comments only

This variation is blank in the Cassette, Disc (flight), Disc (docked), 6502 Second Processor and Master versions.

Electron
 Other entry points:

   ABORT-2              Set the indicator to disarmed (white square)

Code variation 2 of 2Specific to an individual platform

This variation is blank in the Cassette, Disc (flight), Disc (docked), 6502 Second Processor and Master versions.

Electron
 LDY #&09               \ Set Y = &09 so we set the missile to a white square
                        \ (disarmed)

.ABORT

 LDX #&FF               \ Set X to &FF, which is the value of MSTG when we have
                        \ no target lock for our missile

                        \ Fall through into ABORT2 to set the missile lock to
                        \ the value in X, which effectively disarms the missile