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Elite on the BBC Micro and NES

Version analysis of SETXC / DOXC

This code appears in the following versions (click to see it in the source code):

Code variations between these versions are shown below.

Code variation 1 of 5A variation in the comments only

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Name: DOXC
Name: SETXC
Type: Subroutine Category: Text

Code variation 2 of 5A variation in the comments only

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Summary: Move the text cursor to a specific column
Summary: Implement the #SETXC <column> command (move the text cursor to a specific column)

Code variation 3 of 5A variation in the comments only

This variation is blank in the Master version.

This routine is run when the parasite sends a #SETXC <column> command. It updates the text cursor x-coordinate (i.e. the text column) in XC.
Arguments: A The text column

Code variation 4 of 5A variation in the labels only

Tap on a block to expand it, and tap it again to revert.

.DOXC
.SETXC
 STA XC                 \ Store the new text column in XC

Code variation 5 of 5Related to Elite's use of the Tube

Tap on a block to expand it, and tap it again to revert.

RTS \ Return from the subroutine
JMP PUTBACK \ Jump to PUTBACK to restore the USOSWRCH handler and \ return from the subroutine using a tail call