23. Printer output only
    ~~~~~~~~~~~~~~~~~~~
Sometimes it is handy to be able to send text to the printer only, without it
appearing on the VDU screen at the same time. This can be done by using
VDU2,21 to activate the printer, and VDU6,3 to turn it off again and to
restore the VDU drivers. This can cause problems if you try to send anything
other than normal text or figures. Control codes or graphic data may be
corrupted due to the filtering of the "printer ignore character" specified by
*FX6. *FX3,10 and *FX3,0 have a similar effect to these VDU commands.