http://learn.cemetech.net/index.php?action=history&feed=atom&title=Z80%3ADirectives%3ACLEARPAGE 2026-04-28T18:49:07Z Revision history for this page on the wiki MediaWiki 1.43.3 http://learn.cemetech.net/index.php?title=Z80:Directives:CLEARPAGE&diff=197&oldid=prev 2016-02-05T17:11:53Z

<p>Initial automated import</p> <p><b>New page</b></p><div>Clears the data output on a particular page.<br /> <br /> == Syntax ==<br /> <br /> .clearpage page<br /> <br /> == Uses ==<br /> <br /> This directive can be useful to switch to a temporary page, do some assembling, then remove the output data so it doesn&#039;t appear in the output file.<br /> <br /> Use the smallest of two source snippets:<br /> <br /> /* Returns the output size (in bytes) of compiled source */<br /> .function size_of_source(src)<br /> <br /> /* Preserve $ and @ */<br /> old_$_p = :$ \ old_$_v = $:<br /> old_@_p = :@ \ old_@_v = @:<br /> <br /> /* Move to a temporary page (-1) */<br /> :$ = -1<br /> <br /> /* Evaluate the source */<br /> eval(src)<br /> <br /> size_of_source = @ - old_@_v<br /> <br /> /* Clear all output data from temporary page */<br /> .clearpage -1<br /> <br /> /* Restore $ and @ */<br /> :$ = old_$_p \ $: = old_$_v<br /> :@ = old_@_p \ @: = old_@_v<br /> <br /> .endfunction<br /> <br /> /* Uses the smallest of two pieces of source code */<br /> .function use_smallest(src_a, src_b)<br /> <br /> /* Get the size of both snippets */<br /> size_of_src_a = size_of_source(src_a)<br /> size_of_src_b = size_of_source(src_b)<br /> <br /> .if size_of_src_a &lt;= size_of_src_b<br /> use_smallest = size_of_src_a<br /> eval(src_a)<br /> .else<br /> use_smallest = size_of_src_b<br /> eval(src_b)<br /> .endif<br /> <br /> .endfunction<br /> <br /> /* Uses &quot;xor a&quot; and displays 1: */<br /> .echoln use_smallest(&quot;ld a,0&quot;, &quot;xor a&quot;)<br /> <br /> <br /> == See Also ==<br /> <br /> {{lowercase}}<br /> [[Category:Z80 Assembly]]<br /> [[Category:Z80 Heaven]]<br /> [[Category:Z80 Directives]]</div>

Maintenance script