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com(4) [netbsd man page]

COM(4)							   BSD Kernel Interfaces Manual 						    COM(4)

NAME
com -- serial communications interface for RS-232C SYNOPSIS
com0 at isa? port "IO_COM1" irq 4 com1 at isa? port "IO_COM2" irq 3 com* at acpi? com* at cardbus? com* at isapnp? com* at mca? slot ? com* at mhzc? com* at ofisa? com* at pcmcia? com* at pcmcom? com* at pnpbios? index ? com* at puc? port ? com* at xirc? options COM_HAYESP options PPS_SYNC options PPS_TRAILING_EDGE options RND_COM Arm32 com0 at mainbus? base 0x00210fe0 com1 at mainbus? base 0x00210be0 HP 9000/300 and 400 Series com* at dio? scode ? com* at frodo? offset ? HP 9000/700 and 800 Series com* at dino? com* at gsc? com* at ssio? IBM PowerPC 4xx com* at opb? SPARC com* at ebus? com* at obio0 DESCRIPTION
The com driver provides support for NS8250-, NS16450-, and NS16550-based EIA RS-232C (CCITT V.28) communications interfaces. The NS8250 and NS16450 have single character buffers, and the NS16550 has a 16 character buffer. Input and output for each line may set to one of following baud rates; 50, 75, 110, 134.5, 150, 300, 600, 1200, 1800, 2400, 4800, 9600, 19200, 38400, 57600, or 115200, or any other baud rate which is a factor of 115200. The ttyXX devices are traditional dial-in devices; the dtyXX devices are used for dial-out. (See tty(4).) options COM_HAYESP adds support for the Hayes ESP serial board. options PPS_SYNC enables code to use the Data Carrier Detect (DCD) signal line for attachment to an external precision clock source (e.g., GPS, CDMA) which generates a Pulse Per Second (PPS) signal. This is used by ntpd(8) to discipline the system clock, and more accurately count/measure time. See options(4) for more discussion. With options RND_COM enabled, the com driver can be used to collect entropy for the rnd(4) entropy pool. The entropy is generated from interrupt randomness. Arm32 specific If ``flags 1'' is specified, the com driver will not set the MCR_IENABLE bit on the UART. This is mainly for use on AST multiport boards, where the MCR_IENABLE bit is used to control whether or not the devices use a shared interrupt. FILES
/dev/dty00 /dev/dty01 /dev/dty02 /dev/tty00 /dev/tty01 /dev/tty02 DIAGNOSTICS
com%d: %d silo overflows The input ``silo'' has overflowed and incoming data has been lost. com%d: weird interrupt: iir=%x The device has generated an unexpected interrupt with the code listed. SEE ALSO
acpi(4), ast(4), cardbus(4), isa(4), isapnp(4), mca(4), mhzc(4), ofisa(4), options(4), pcmcia(4), pcmcom(4), pnpbios(4), puc(4), rtfps(4), tty(4), xirc(4), ntpd(8) HISTORY
The com driver was originally derived from the HP9000/300 dca driver. BUGS
Data loss is possible on busy systems with unbuffered UARTs at high speed. The name of this driver and the constants which define the locations of the various serial ports are holdovers from DOS. BSD
June 7, 2011 BSD

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BOCA(4) 						   BSD Kernel Interfaces Manual 						   BOCA(4)

NAME
boca -- multiplexing serial communications interface SYNOPSIS
For 4-port BB1004 boards: boca0 at isa? port 0x100 irq 5 com2 at boca? slave ? com3 at boca? slave ? com4 at boca? slave ? com5 at boca? slave ? For 8-port BB1008 boards: boca0 at isa? port 0x100 irq 5 com2 at boca? slave ? com3 at boca? slave ? com4 at boca? slave ? com5 at boca? slave ? com6 at boca? slave ? com7 at boca? slave ? com8 at boca? slave ? com9 at boca? slave ? For 16-port BB2016 boards: boca0 at isa? port 0x100 irq 5 com2 at boca? slave ? com3 at boca? slave ? com4 at boca? slave ? com5 at boca? slave ? com6 at boca? slave ? com7 at boca? slave ? com8 at boca? slave ? com9 at boca? slave ? boca1 at isa? port 0x140 irq 5 com10 at boca? slave ? com11 at boca? slave ? com12 at boca? slave ? com13 at boca? slave ? com14 at boca? slave ? com15 at boca? slave ? com16 at boca? slave ? com17 at boca? slave ? (The BB2016 is functionally equivalent to two BB1008 boards, and is configured as such.) DESCRIPTION
The boca driver provides support for BOCA Research BB1004, BB1008 and BB2016 boards that multiplex together up to four, eight or sixteen EIA RS-232C (CCITT V.28) communications interfaces. Each boca device is the master device for up to eight com devices. The kernel configuration specifies these com devices as slave devices of the boca device, as shown in the synopsis. The slave ID given for each com device determines which bit in the interrupt multiplexing regis- ter is tested to find interrupts for that device. The port specification for the boca device is used to compute the base addresses for the com subdevices and the port for the interrupt multiplexing register. FILES
/dev/tty?? SEE ALSO
com(4) HISTORY
The boca driver was written by Charles Hannum, based on the ast driver and source code from David Muir Sharnoff. David wishes to acknowledge the assistance of Jason Venner in determining how to use the BOCA boards. BSD
January 3, 1995 BSD
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