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⌂ ∞ Elite on the BBC Micro and NES

Loader: INBAY

[Elite-A, Docked]

       Name: INBAY                                                   [Show more]
       Type: Subroutine
   Category: Loader
    Summary: Set the break handler and go to the docking bay without showing
             the tunnel or ship hangar, or checking mission progress

    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * DOENTRY calls INBAY




.INBAY

                        \ --- Mod: Code removed for Elite-A: ------------------>

\ LDX #0                \ This code is never run, but it takes up the same
\ LDY #0                \ number of bytes as the INBAY routine in the flight
\ JSR &8888             \ code, so if the flight code *LOADs the docked code in
\ JMP SCRAM             \ its own version of the INBAY routine, then execution
\                       \ will fall through into the DOBEGIN routine below once
\                       \ the docked binary has loaded
\                       \
\                       \ This enables the docked code to choose whether to load
\                       \ the docked code and jump to DOBEGIN to restart the
\                       \ game (in which case the flight code simply *LOADs the
\                       \ docked code), or whether to dock with the space
\                       \ station and continue the game (in which case the
\                       \ flight code *RUNs the docked code, which has an
\                       \ execution address of S% at the start of the docked
\                       \ code, which contains a JMP DOENTRY instruction)

                        \ --- And replaced by: -------------------------------->

 JSR BRKBK              \ Call BRKBK to set BRKV to point to the BRBR routine

 JMP icode_set          \ Jump to icode_set to reset a number of flight
                        \ variables and workspaces and go to the docking bay
                        \ (i.e. show the Status Mode screen)

 EQUB 0                 \ This pads the INBAY routine so it takes up the same
                        \ number of bytes as the INBAY routine in the flight
                        \ code, so if the flight code *LOADs the docked code in
                        \ its own version of the INBAY routine, then execution
                        \ will fall through into the code below once the docked
                        \ binary has loaded
                        \
                        \ This enables the docked code to choose whether to load
                        \ the docked code and jump to DOBEGIN to restart the
                        \ game (in which case the flight code simply *LOADs the
                        \ docked code), or whether to dock with the space
                        \ station and continue the game (in which case the
                        \ flight code *RUNs the docked code, which has an
                        \ execution address of S% at the start of the docked
                        \ code, which contains a JMP DOENTRY instruction)

                        \ If we get here then we have loaded the docked code and
                        \ fallen through to this point, so we need to restart
                        \ the game

 LDA #0                 \ Call SCRAM to set save_lock to 0 (i.e. this is a new
 JSR SCRAM              \ game) and set the break handler

 JSR RES2               \ Reset a number of flight variables and workspaces

 JMP TT170              \ Jump to TT170 to start the game

                        \ --- End of replacement ------------------------------>