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UCOM(4) NetBSD Kernel Interfaces Manual UCOM(4)
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Maintained for NetBSD
by Kimmo Suominen.
Based on man-cgi by Panagiotis Christias.
ucom -- USB tty support
ucom* at u3g?
ucom* at uark?
ucom* at ubsa?
ucom* at uchcom?
ucom* at uftdi?
ucom* at ugensa?
ucom* at uhmodem?
ucom* at uipaq?
ucom* at ukyopon?
ucom* at umcs? portno ?
ucom* at umct?
ucom* at umodem?
ucom* at uplcom?
ucom* at uslsa?
ucom* at uvisor? portno ?
ucom* at uvscom?
The ucom driver attaches to USB modems, serial ports, and other devices
that need to look like a tty. The ucom driver shows a behaviour like a
tty(4). This means that normal programs such as tip(1) or pppd(8) can be
used to access the device.
The portno locator can be used to decide which port to use for device
that have multiple external ports.
Note that while ucom supports the (undocumented) pulse-per-second API
normally used on conventional serial ports, USB serial devices typically
have a varying latency around 1 ms due to the USB frame structure.
The ttyXX devices are traditional dial-in devices; the dtyXX devices are
used for dial-out. (See tty(4).)
tty(4), u3g(4), ubsa(4), uchcom(4), uftdi(4), ugensa(4), uhmodem(4),
uipaq(4), ukyopon(4), umct(4), umodem(4), uplcom(4), usb(4), uslsa(4),
The ucom driver appeared in NetBSD 1.5.
NetBSD 8.1 September 29, 2016 NetBSD 8.1