1.\" $OpenBSD: cy.4,v 1.5 2001/06/22 12:15:44 mpech Exp $ 2.\" 3.\" Copyright (c) 1993 Andrew Herbert. 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. The name Andrew Herbert may not be used to endorse or promote products 15.\" derived from this software without specific prior written permission. 16.\" 17.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27.\" 28.Dd October 5, 1993 29.Dt CY 4 30.Os 31.Sh NAME 32.Nm cy 33.Nd Cyclades Cyclom-{4, 8, 16}Y asynchronous comms board device driver 34.Sh SYNOPSIS 35.Cd "cy0 at isa? tty irq 10 iomem 0xdc000 iosiz 8192 vector cyintr" 36.Cd "cy1 at pci?" 37.Sh DESCRIPTION 38This driver provides an interface to Cyclades Cyclom-4Y, Cyclom-8Y and 39Cyclom-16Y asynchronous multiport serial boards. 40These boards are based around Cirrus Logic CD1400 communication controllers. 41.Pp 42The device minor numbers for this driver are encoded as follows: 43.Pp 44.Bd -literal 45 c c x x u u u u - bits in the minor device number 46 47 bits meaning 48 ---- ------- 49 uuuu physical serial line (i.e., unit) to use 50 0-7 on a cyclom-8Y, 0-15 on a cyclom-16Y 51 52 xx unused 53 54 cc carrier control mode 55 00 complete hardware carrier control of the tty. 56 DCD must be high for the open(2) to complete. 57 01 reserved 58 10 carrier ignored until a high->low transition 59 11 carrier completed ignored 60.Ed 61.Sh DIAGNOSTICS 62.Bl -diag 63.It "cy%d: tty input queue overflow" 64Incoming characters have been discarded due to a buffer overflow. 65This is caused by the process in control of the device not 66.Xr read 2 Ns No 'ing 67characters fast enough. 68.It "cy%d: receive fifo overrun" 69Incoming characters have been discarded due to a CD1400 channel overrun. 70This is caused by interrupts not being serviced sufficiently quickly to prevent 71the 12 byte receive FIFO on a serial channel from overflowing. 72Reducing the value of the \fIRxFifoThreshold\fR #define from 8 to something 73smaller may help slow machines avoid this problem. 74The driver must have been compiled with the \fILogOverruns\fR option 75defined (the default) in order for this condition to be logged. 76.El 77.Sh SEE ALSO 78.Xr com 4 , 79.Xr termios 4 , 80.Xr tty 4 81.Sh AUTHORS 82The driver was written by Andrew Herbert <andrew@werple.apana.org.au>, and 83is still under development (from time to time :-). 84.Sh HISTORY 85Some ideas for the architecture of this driver's two-layer processing model 86were derived from the fas 2.10 driver by Uwe Doering 87<gemini@geminix.in-berlin.de> and the high-performance com driver by Bruce 88Evans <bde@kralizec.zeta.org.au>. 89.Pp 90This work was made possible through the donation of a Cyclom-8Y board by the 91manufacturer, Cyclades Corporation. 92However, neither Cyclades nor the author make any warranties regarding 93this software, nor guarantees of support. 94.Sh BUGS 95There is currently no BREAK handling - breaks are ignored. 96There is no support for bad-character reporting, except via PARMRK. 97The Cyclom-[48]Y boards do not listen to the RTS signal for receiver flow 98control. 99FIFO overruns are only logged when the termios IGNPAR setting is enabled. 100