Save and load: CHECK2

       Name: CHECK2                                                  [Show more]
       Type: Subroutine
   Category: Save and load
    Summary: Calculate the third checksum for the last saved commander data
             block (Commodore 64 and Apple II versions only)
    Context: See this subroutine in context in the source code
 References: No direct references to this subroutine in this source file


.CHECK2

\LDX #NT%-3             \ These instructions are commented out in the original
\                       \ source (they are from the Commodore 64 and Apple II
\CLC                    \ versions, and implement the third commander checksum
\                       \ which the Master version doesn't have)
\TXA
\
\.QU2L2
\
\STX T
\EOR T
\ROR A
\
\ADC NA%+7,X
\
\EOR NA%+8,X
\
\DEX
\
\BNE QU2L2
\
\RTS