1.\" $OpenBSD: addcom.4,v 1.2 2001/07/18 10:47:13 mpech Exp $ 2.\" 3.\" Copyright (c) 2001 Jason L. Wright (jason@thought.net) 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by Jason L. Wright 17.\" 4. The name of the author may not be used to endorse or promote products 18.\" derived from this software without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 21.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 22.\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 23.\" DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, 24.\" INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 25.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 26.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 28.\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 29.\" ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30.\" POSSIBILITY OF SUCH DAMAGE. 31.\" 32.\" 33.Dd July 16, 2001 34.Dt ADDCOM 4 35.Os 36.Sh NAME 37.Nm addcom 38.Nd multiplexing serial communications interface 39.Sh SYNOPSIS 40.Cd "addcom0 at isa? port 0x108 irq 5" 41.Cd "com* at addcom? slave ?" 42.Sh DESCRIPTION 43The 44.Nm 45driver provides support for Addonics FlexPort 8/S (and probably FlexPort 4/S) 46boards that multiplex together up to eight (or four) 47.Tn EIA 48.Tn RS-232C 49.Pf ( Tn CCITT 50.Tn V.28 ) 51communications interfaces. 52.Pp 53Each 54.Nm 55device is the master device for up to eight 56.Nm com 57devices. 58The kernel configuration specifies these 59.Nm com 60devices as slave devices of the 61.Nm 62device, as shown in the synopsis. 63The slave ID given for each 64.Nm com 65device determines which bit in the interrupt multiplexing register is 66tested to find interrupts for that device. 67The 68.Tn port 69specification for the 70.Nm 71device is used to compute the base addresses for the 72.Nm com 73subdevices. 74The port for the interrupt multiplexing register is fixed, 75so it is doubtful that more than one 76.Nm 77can be used in a machine. 78.Sh FILES 79.Bl -tag -width Pa 80.It Pa /dev/tty?? 81.El 82.Sh SEE ALSO 83.Xr com 4 84.Sh HISTORY 85.Ox 86support for 87.Nm 88devices first appeared in 89.Ox 3.0 . 90