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⌂ ∞ ▽ Elite on the BBC Micro and NES

Text: POSWRCH

[6502 Second Processor version, I/O processor]

       Name: POSWRCH                                                 [Show more]
       Type: Subroutine
   Category: Text
    Summary: Print a character on the printer only

    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * prilf calls POSWRCH
             * printer calls POSWRCH
             * tosend calls POSWRCH




 Arguments:

   A                    The character to send to the printer



.POSWRCH

 PHA                    \ Store A on the stack so we can retrieve it after the
                        \ following call to NVOSWRCH

 LDA #1                 \ Send ASCII 1 to the printer using the non-vectored
 JSR NVOSWRCH           \ OSWRCH, which means "send the next character to the
                        \ printer only"

 PLA                    \ Retrieve A from the stack

 JMP NVOSWRCH           \ Send the character in A to the printer using the
                        \ non-vectored OSWRCH, which prints the character on the
                        \ printer, and return from the subroutine using a tail
                        \ call