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Elite on the BBC Micro and NES

Text: label

[6502 Second Processor version]

Name: label [Show more] Type: Subroutine Category: Text Summary: Send a two-byte OSWRCH command to the I/O processor
Context: See this subroutine in context in the source code References: This subroutine is called as follows: * DOCOL calls label * DOVDU19 calls label

This routine sends a command to the I/O processor, along with the parameter byte from the top of the stack.
Arguments: A The command byte to send to the I/O processor Top of stack The parameter to send to the I/O processor
.label JSR OSWRCH \ Send the command byte in A to the I/O processor PLA \ Retrieve the parameter from the stack JMP OSWRCH \ Send the parameter in A to the I/O processor, and \ return from the subroutine using a tail call