Source string Read only

(itstool) path: answer/para
105/1050
Context English State
The third serial port, <filename>sio2</filename>, or <filename>COM3</filename>, is on <filename>/dev/cuad2</filename> for dial-out devices, and on <filename>/dev/ttyd2</filename> for dial-in devices. What is the difference between these two classes of devices?
When opening <filename>/dev/ttydX</filename> in blocking mode, a process will wait for the corresponding <filename>cuadX</filename> device to become inactive, and then wait for the carrier detect line to go active. When the <filename>cuadX</filename> device is opened, it makes sure the serial port is not already in use by the <filename>ttydX</filename> device. If the port is available, it steals it from the <filename>ttydX</filename> device. Also, the <filename>cuadX</filename> device does not care about carrier detect. With this scheme and an auto-answer modem, remote users can log in and local users can still dial out with the same modem and the system will take care of all the conflicts.
How do I enable support for a multi-port serial card?
The section on kernel configuration provides information about configuring the kernel. For a multi-port serial card, place an <citerefentry><refentrytitle>sio</refentrytitle><manvolnum>4</manvolnum></citerefentry> line for each serial port on the card in the <citerefentry vendor="current"><refentrytitle>device.hints</refentrytitle><manvolnum>5</manvolnum></citerefentry> file. But place the IRQ specifiers on only one of the entries. All of the ports on the card should share one IRQ. For consistency, use the last serial port to specify the IRQ. Also, specify the following option in the kernel configuration file:
options COM_MULTIPORT
The following <filename>/boot/device.hints</filename> example is for an AST 4-port serial card on IRQ 12:
hint.sio.4.at="isa"
hint.sio.4.port="0x2a0"
hint.sio.4.flags="0x701"
hint.sio.5.at="isa"
hint.sio.5.port="0x2a8"
hint.sio.5.flags="0x701"
hint.sio.6.at="isa"
hint.sio.6.port="0x2b0"
hint.sio.6.flags="0x701"
hint.sio.7.at="isa"
hint.sio.7.port="0x2b8"
hint.sio.7.flags="0x701"
hint.sio.7.irq="12"
The flags indicate that the master port has minor number <literal>7</literal> (<literal>0x700</literal>), and all the ports share an IRQ (<literal>0x001</literal>).
Can I set the default serial parameters for a port?
See the <link xlink:href="@@URL_RELPREFIX@@/doc/en_US.ISO8859-1/books/handbook/serial.html#serial-hw-config">Serial Communications</link> section in the FreeBSD Handbook.
Why can I not run <command>tip</command> or <command>cu</command>?

Loading…

None

New source string

FreeBSD Doc / books_faqEnglish

New source string 3 months ago
Browse all component changes

Glossary

English English
No related strings found in the glossary.

Source information

Source string comment
(itstool) path: answer/para
Labels
No labels currently set.
Flags
read-only
Source string location
book.translate.xml:5326
Source string age
3 months ago
Translation file
, string 860