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.\" $FreeBSD$ 29.\" 30.Dd February 14, 1999 31.Dt LPT 4 32.Os FreeBSD 33.Sh NAME 34.Nm lpt 35.Nd 36Generic printer device driver 37.Sh SYNOPSIS 38.Cd "controller ppbus0" 39.Cd "device lpt0 at ppbus?" 40.Pp 41.Cd "controller ppc0 at isa? port" \&"IO_LPT1\&" tty irq 7 42.Cd "controller ppc1 at isa? port" \&"IO_LPT2\&" tty irq 7 43.Cd "controller ppc2 at isa? port" \&"IO_LPT3\&" tty irq 7 44.Pp 45For BIOS-probed ports: 46.Cd "controller ppc0 at isa? port? tty irq 7" 47.Pp 48For polled ports: 49.Cd "controller ppc0 at isa? port? tty" 50.Cd "controller ppc1 at isa? port" \&"IO_LPT2\&" tty 51.Pp 52For DMA capable parallel port: 53.Cd "controller ppc0 at isa? port? tty irq 7 drq 1" 54.Sh DESCRIPTION 55The current 56.Em lpt 57driver is the port of the original lpt driver to the 58.Xr ppbus 4 59system. 60.Pp 61One purpose of this port was to allow parallel port sharing with other 62parallel devices. Secondly, inb()/outb() calls have been replaced by ppbus 63function calls. lpt is now arch-independent thanks to the ppbus interface. See 64.Xr ppbus 4 65for more info about the ppbus system. 66.Pp 67The parallel port bus is allocated by lpt when the printer device is opened 68and released only when the transfer is completed: either when the device 69is closed or when the entire buffer is sent in interrupt driven mode. 70.Pp 71The driver can be configured to be either interrupt-driven, or 72to poll the printer. Ports that are configured to be 73interrupt-driven can be switched to polled mode by using the 74.Xr lptcontrol 8 75command. 76.Pp 77Depending on your hardware, extended capabilities may be configured with the 78.Xr lptcontrol 8 79command. With an ECP/ISA port, you can take advantage 80of FIFO and DMA. 81.Pp 82In order to retrieve printer info from /dev/lpt0, just apply the 83.Nm cat 84command to the device. If the printer supports IEEE1284 nibble mode and has 85data to send to the host, you'll get it. 86.Sh SEE ALSO 87.Xr ppbus 4 , 88.Xr lptcontrol 8 89.Sh HISTORY 90This driver replaces the functionality of the lpa 91driver, which is now defunct. 92.Sh FILES 93.Bl -tag -width Pa -compact 94.It Pa /dev/lpt0 95first parallel port driver 96.El 97.Sh BUGS 98There are lots of them, especially in cheap parallel port implementations. 99.Pp 100It is only possible to open a lpt port when a printer is connected and 101on-line, making it impossible to run 102.Xr lptcontrol 8 103when there is no printer connected. 104.Pp 105Please, ensure the 106.Xr ppc 4 107entry in you MACHINE file has the tty interrupt mask. 108.Pp 109This driver could still stand a rewrite. 110