UCHCOM(4)              FreeBSD Kernel Interfaces Manual              UCHCOM(4)

NAME

     uchcom - WinChipHead CH9102/CH343/CH341/CH340 USB to serial UART driver

SYNOPSIS

     device usb
     device ucom
     device uchcom

     In rc.conf(5):
     kld_list="uchcom"

     In sysctl.conf(5):
     hw.usb.uchcom.debug=1

DESCRIPTION

     The uchcom driver provides support for the WinChipHead USB to serial UART
     adapters.  If the appropriate hardware is detected, the driver will be
     loaded automatically by devmatch(8).  To load the driver manually, add it
     to the kld_list in rc.conf(5), or use kldload(8) at runtime.  The device
     is accessed through the ucom(4) driver, which makes it behave like a
     tty(4).

     Call out through this interface with applications like cu(1) or tip(1).

HARDWARE

     The uchcom driver supports the following USB to serial UART controllers:

     o   WinChipHead CH9102 (max 6Mbps)
     o   WinChipHead CH343 (max 6Mbps)
     o   WinChipHead CH341 (max 2Mbps)
     o   WinChipHead CH340 (max 2Mbps)

SYSCTL VARIABLES

     These settings can be entered in the loader(8) prompt, set in
     loader.conf(5), sysctl.conf(5), or changed at runtime with sysctl(8):

     hw.usb.uchcom.debug  Enable debugging messages, default `0'

FILES

     /dev/ttyU*       for callin ports
     /dev/ttyU*.init
     /dev/ttyU*.lock  corresponding callin initial-state and lock-state
                      devices

     /dev/cuaU*       for callout ports
     /dev/cuaU*.init
     /dev/cuaU*.lock  corresponding callout initial-state and lock-state
                      devices

SEE ALSO

     cu(1), tty(4), ucom(4), usb(4)

HISTORY

     The uchcom driver appeared in FreeBSD 8.0 from NetBSD 5.0.

FreeBSD 15.1-STABLE-HBSD         June 25, 2025                       UCHCOM(4)