cy man page on OpenBSD

Man page or keyword search:  
man Server   11362 pages
apropos Keyword Search (all sections)
Output format
OpenBSD logo
[printable version]

CY(4)			  OpenBSD Programmer's Manual			 CY(4)

     cy - Cyclades Cyclom-{4, 8, 16}Y asynchronous comms board device driver

     cy0 at isa? iomem 0xd4000 irq 12
     cy* at pci?

     This driver provides an interface to Cyclades Cyclom-4Y, Cyclom-8Y and
     Cyclom-16Y asynchronous multiport serial boards.  These boards are based
     around Cirrus Logic CD1400 communication controllers.

     The device minor numbers for this driver are encoded as follows:

	 d c c u u u u u    - bits in the minor device number

	 bits	 meaning
	 ----	 -------
	 uuuuu	 physical serial line (i.e., unit) to use
		     0-7 on a cyclom-8Y, 0-15 on a cyclom-16Y

	 cc	 card number

	 d	 dial-out flag

     cy%d: tty input queue overflow  Incoming characters have been discarded
     due to a buffer overflow.	This is caused by the process in control of
     the device not read(2)'ing characters fast enough.

     cy%d: receive fifo overrun	 Incoming characters have been discarded due
     to a CD1400 channel overrun.  This is caused by interrupts not being
     serviced sufficiently quickly to prevent the 12 byte receive FIFO on a
     serial channel from overflowing.  Reducing the value of the
     RxFifoThreshold #define from 8 to something smaller may help slow
     machines avoid this problem.  The driver must have been compiled with the
     LogOverruns option defined (the default) in order for this condition to
     be logged.

     com(4), intro(4), isa(4), pci(4), termios(4), tty(4)

     Some ideas for the architecture of this driver's two-layer processing
     model were derived from the fas 2.10 driver by Uwe Doering
     <> and the high-performance com driver by
     Bruce Evans <>.

     This work was made possible through the donation of a Cyclom-8Y board by
     the manufacturer, Cyclades Corporation.  However, neither Cyclades nor
     the author make any warranties regarding this software, nor guarantees of

     The driver was written by Andrew Herbert <>.

     There is currently no BREAK handling - breaks are ignored.	 There is no
     support for bad-character reporting, except via PARMRK.  The Cyclom-[48]Y
     boards do not listen to the RTS signal for receiver flow control.	FIFO
     overruns are only logged when the termios IGNPAR setting is enabled.

OpenBSD 4.9			 May 31, 2007			   OpenBSD 4.9

List of man pages available for OpenBSD

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
Vote for polarhome
Free Shell Accounts :: the biggest list on the net