UCOM(4) | Device Drivers Manual | UCOM(4)

# NAME

`ucom` —
USB tty support

# SYNOPSIS

`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?`
`ucom* at uxrcom?`

# DESCRIPTION

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).)

# FILES

/dev/dtyU?
/dev/ttyU?

# SEE ALSO

tty(4), u3g(4), uark(4), ubsa(4), uchcom(4), uftdi(4), ugensa(4), uhmodem(4), uipaq(4), ukyopon(4), umcs(4), umct(4), umodem(4), uplcom(4), usb(4), uslsa(4), uvisor(4), uvscom(4), uxrcom(4)

# HISTORY

The `ucom` driver appeared in NetBSD 1.5.

May 5, 2019 | NetBSD 9.5