1.\" 2.\" Copyright (c) 1993 Christopher G. Demetriou 3.\" Copyright (c) 1994 Geoffrey M. Rehmet 4.\" Copyright (c) 1999 Nicolas Souchu 5.\" All rights reserved. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" 29.Dd February 14, 1999 30.Dt LPT 4 31.Os FreeBSD 32.Sh NAME 33.Nm lpt 34.Nd 35Generic printer device driver 36.Sh SYNOPSIS 37.Cd "controller ppbus0" 38.Cd "device lpt0 at ppbus?" 39.Pp 40.Cd "controller ppc0 at isa? port" \&"IO_LPT1\&" tty irq 7 41.Cd "controller ppc1 at isa? port" \&"IO_LPT2\&" tty irq 7 42.Cd "controller ppc2 at isa? port" \&"IO_LPT3\&" tty irq 7 43.Pp 44For BIOS-probed ports: 45.Cd "controller ppc0 at isa? port? tty irq 7" 46.Pp 47For polled ports: 48.Cd "controller ppc0 at isa? port? tty" 49.Cd "controller ppc1 at isa? port" \&"IO_LPT2\&" tty 50.Pp 51For DMA capable parallel port: 52.Cd "controller ppc0 at isa? port? tty irq 7 drq 1" 53.Sh DESCRIPTION 54The current 55.Em lpt 56driver is the port of the original lpt driver to the 57.Xr ppbus 4 58system. 59.Pp 60One purpose of this port was to allow parallel port sharing with other 61parallel devices. Secondly, inb()/outb() calls have been replaced by ppbus 62function calls. lpt is now arch-independent thanks to the ppbus interface. See 63.Xr ppbus 4 64for more info about the ppbus system. 65.Pp 66The parallel port bus is allocated by lpt when the printer device is opened 67and released only when the transfer is completed: either when the device 68is closed or when the entire buffer is sent in interrupt driven mode. 69.Pp 70The driver can be configured to be either interrupt-driven, or 71to poll the printer. Ports that are configured to be 72interrupt-driven can be switched to polled mode by using the 73.Xr lptcontrol 8 74command. 75.Pp 76Depending on your hardware, extended capabilities may be configured with the 77.Xr lptcontrol 8 78command. With an ECP/ISA port, you can take advantage 79of FIFO and DMA. 80.Pp 81In order to retrieve printer info from /dev/lpt0, just apply the 82.Nm cat 83command to the device. If the printer supports IEEE1284 nibble mode and has 84data to send to the host, you'll get it. 85.Sh SEE ALSO 86.Xr ppbus 4 , 87.Xr lptcontrol 8 88.Sh HISTORY 89This driver replaces the functionality of the lpa 90driver, which is now defunct. 91.Sh FILES 92.Bl -tag -width Pa -compact 93.It Pa /dev/lpt0 94first parallel port driver 95.El 96.Sh BUGS 97There are lots of them, especially in cheap parallel port implementations. 98.Pp 99It is only possible to open a lpt port when a printer is connected and 100on-line, making it impossible to run 101.Xr lptcontrol 8 102when there is no printer connected. 103.Pp 104Please, ensure the 105.Xr ppc 4 106entry in you MACHINE file has the tty interrupt mask. 107.Pp 108This driver could still stand a rewrite. 109