[net.micro] What does this undocumented op-code do?

CENT.MBECK%MIT-OZ@MIT-MC.ARPA (01/21/84)

From:  Mark Becker <CENT.MBECK%MIT-OZ@MIT-MC.ARPA>

     SIMTEL20 MICRO:<CPM.MACLIB>Z80EXT.LIB has a bunch of formerly
undocumented Z-80 opcodes in it.  I was going through the pile a day
or two ago when I ran into the last one in the file.

     What is the SLAS macro supposed to do?  I can't seem to infer it's
operation using ZSID...

	Your help is appreciated..
						Mark
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