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⌂ ∞ Elite on the BBC Micro

Save and load: DODOSVN

[6502 Second Processor version]

       Name: DODOSVN                                                 [Show more]
       Type: Subroutine
   Category: Save and load
    Summary: Set the SVN ("save in progress") flag by sending a #DOsvn command
             to the I/O processor

    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * QUS1 calls DODOSVN
             * SCLI2 calls DODOSVN
             * backtonormal calls DODOSVN




 Arguments:

   A                    The new value of SVN



.DODOSVN

 PHA                    \ Store A and Y on the stack
 PHY

 LDA #DOsvn             \ Send the first part of a #DOsvn command to the I/O
 JSR OSWRCH             \ processor

 PLY                    \ Retrieve the values of A and Y from the stack
 PLA

 JSR OSWRCH             \ Send the new value of SVN to the I/O processor, so
                        \ we've now sent a #DOsvn  command

                        \ Fall through into CLDELAY to pause for 1280 empty
                        \ loops