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⌂ ∞ ▽ Elite on the 6502

Loader: Elite loader (Part 2 of 2)

[BBC Micro disc version, Loader 2]

       Name: Elite loader (Part 2 of 2)                              [Show more]
       Type: Subroutine
   Category: Loader
    Summary: Load and run the ELITE4 loader

    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * MPL calls via ENTRY2




 Other entry points:

   ENTRY2               Re-entry point to continue the loading process from the
                        MPL routine



.ENTRY2

 LDA #15                \ Call OSBYTE with A = 15 and Y = 0 to flush the input
 LDY #0                 \ buffer
 JSR OSBYTE

 LDX #LO(MESS1)         \ Set (Y X) to point to MESS1 ("LOAD Elite4")
 LDY #HI(MESS1)

 JSR OSCLI              \ Call OSCLI to run the OS command in MESS1, which loads
                        \ the ELITE4 binary to its load address of &1900

 LDA #21                \ Call OSBYTE with A = 21 and X = 0 to flush the
 LDX #0                 \ keyboard buffer
 JSR OSBYTE

 LDA #201               \ Call OSBYTE with A = 201, X = 1 and Y = 1 to re-enable
 LDX #1                 \ the keyboard, which we disabled in the first loader
 LDY #1
 JSR OSBYTE

 JMP &197B              \ Jump to the start of the ELITE4 loader code at &197B

 SKIP 15                \ These bytes appear to be unused