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⌂ ∞ Elite on the BBC Micro and NES

Text: write_msg3

[Elite-A, Parasite]

       Name: write_msg3                                              [Show more]
       Type: Subroutine
   Category: Text
    Summary: Print an extended recursive token from the msg_3 token table
  Deep dive: The Encyclopedia Galactica

    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * controls calls write_msg3
             * equip_data calls write_msg3
             * menu calls write_msg3
             * ships_ag calls write_msg3
             * write_card calls write_msg3




 Arguments:

   A                    The recursive token to be printed, in the range 0-255



 Returns:

   A                    A is preserved

   Y                    Y is preserved

   V(1 0)               V(1 0) is preserved



.write_msg3

 PHA                    \ Store A on the stack, so we can retrieve it later

 TAX                    \ Copy the token number from A into X

 TYA                    \ Store Y on the stack
 PHA

 LDA V                  \ Store V(1 0) on the stack
 PHA
 LDA V+1
 PHA

 LDA #LO(msg_3)         \ Set V to the low byte of msg_3
 STA V

 LDA #HI(msg_3)         \ Set A to the high byte of msg_3

 BNE DTEN               \ Call DTEN to print token number X from the msg_3
                        \ table and restore the values of A, Y and V(1 0) from
                        \ the stack, returning from the subroutine using a tail
                        \ call (this BNE is effectively a JMP as A is never
                        \ zero)