Save and load: QUS1

       Name: QUS1                                                    [Show more]
       Type: Subroutine
   Category: Save and load
    Summary: Save or load the commander file
  Deep dive: Commander save files
    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * LOD calls QUS1
             * SVE calls QUS1


 The filename should be stored at INWK, terminated with a carriage return (13).
 The routine should be called with Y set to &C.


 Arguments:

   A                    File operation to be performed. Can be one of the
                        following:

                          * 0 (save file)

                          * &FF (load file)

   Y                    Points to the page number containing the OSFILE block,
                        which must be &C because that's where the pointer to the
                        filename in INWK is stored below (by the STX &0C00
                        instruction)


.QUS1

 PHA                    \ Store A on the stack so we can restore it after the
                        \ call to GTDRV

 JSR GTDRV              \ Get an ASCII disc drive number from the keyboard in A,
                        \ setting the C flag if an invalid drive number was
                        \ entered

 STA INWK+1             \ Store the ASCII drive number in INWK+1, which is the
                        \ drive character of the filename string ":0.E."

 PLA                    \ Restore A from the stack

 BCS QUR                \ If the C flag is set, then an invalid drive number was
                        \ entered, so jump to QUR to return from the subroutine

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

 STA save_lock          \ Set save_lock to 0 (when we save a file) or &FF (when
                        \ we load a file) to indicate:
                        \
                        \   * 0 = last file operation was a save
                        \
                        \   * &FF = last file operation was a load

                        \ --- End of added code ------------------------------->

 LDX #INWK              \ Store a pointer to INWK at the start of the block at
 STX &0C00              \ &0C00, storing #INWK in the low byte because INWK is
                        \ in zero page

 LDX #0                 \ Set (Y X) = &0C00
 LDY #&C

 JSR OSFILE             \ Call OSFILE to do the file operation specified in
                        \ &0C00 (i.e. save or load a file depending on the value
                        \ of A)

 CLC                    \ Clear the C flag

.QUR

 RTS                    \ Return from the subroutine