Int 21 Fn FFBC - Topware Network Os V5.10+ - Cancel Topshow Function [N]
AX = FFBCh
CH = printer number (00h LPT1, 01h LPT2, 02h LPT3)
CL = printer server station address or 00h for local printer
Return: AL = status (00h successful, else failed)
See Also: AX=FFBBh