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UFTDI(4)               FreeBSD Kernel Interfaces Manual               UFTDI(4)

     uftdi - USB support for serial adapters based on the FTDI family of USB
     serial adapter chips.

     To compile this driver into the kernel, place the following lines in your
     kernel configuration file:

           device usb
           device ucom
           device uftdi

     Alternatively, to load the driver as a module at boot time, place the
     following line in loader.conf(5):


     The uftdi driver provides support for various serial adapters based on
     the following FTDI chips:


     The device is accessed through the ucom(4) driver which makes it behave
     like a tty(4).

     Many of the supported chips provide additional functionality such as
     bitbang mode and the MPSSE engine for serial bus emulation.  The uftdi
     driver provides access to that functionality with the following ioctl(2)
     calls, defined in <dev/usb/uftdiio.h>:

             Reset the channel to its default configuration, flush RX and TX

             Flush the RX FIFO.

             Flush the TX FIFO.

     UFTDIIOC_SET_BITMODE (struct uftdi_bitmode)
             Put the channel into the operating mode specified in mode, and
             set the pins indicated by ones in iomask to output mode.  The
             mode must be one of the uftdi_bitmodes values.  Setting mode to
             UFTDI_BITMODE_NONE returns the channel to standard UART mode.

             enum uftdi_bitmodes
                     UFTDI_BITMODE_ASYNC = 0,
                     UFTDI_BITMODE_MPSSE = 1,
                     UFTDI_BITMODE_SYNC = 2,
                     UFTDI_BITMODE_CPU_EMUL = 3,
                     UFTDI_BITMODE_FAST_SERIAL = 4,
                     UFTDI_BITMODE_CBUS = 5,
                     UFTDI_BITMODE_NONE = 0xff,

             struct uftdi_bitmode
                     uint8_t mode;
                     uint8_t iomask;

             Manuals and application notes published by FTDI describe these
             modes in detail.  To use most of these modes, you first put the
             channel into the desired mode, then you read(2) and write(2) data
             which either reflects pin state or is interpreted as MPSSE
             commands and parameters, depending on the mode.

     UFTDIIOC_GET_BITMODE (struct uftdi_bitmode)
             Return the current bitbang mode in the mode member, and the state
             of the DBUS0..DBUS7 pins at the time of the call in the iomask
             member.  The pin state can be read while the chip is in any mode,
             including UFTDI_BITMODE_NONE (UART) mode.

             Set the character which is inserted into the buffer to mark the
             point of an error such as FIFO overflow.

             Set the character which causes a partial FIFO full of data to be
             returned immediately even if the FIFO is not full.

             Set the amount of time to wait for a full FIFO, in milliseconds.
             If more than this much time elapses without receiving a new
             character, any characters in the FIFO are returned.

             Get the current value of the latency timer.

             Get the hardware revision number.  This is the bcdDevice value
             from the usb_device_descriptor.

     UFTDIIOC_READ_EEPROM (struct uftdi_eeio)
             Read one or more words from the configuration eeprom.  The FTDI
             chip performs eeprom I/O in 16-bit words.  Set offset and length
             to values evenly divisible by two before the call, and the data
             array will contain the requested values from eeprom after the

             struct uftdi_eeio
                     uint16_t offset;
                     uint16_t length;
                     uint16_t data[64];

             The FT232R chip has an internal eeprom.  An external serial
             eeprom is optional on other FTDI chips.  The eeprom may contain
             64, 128, or 256 words, depending on the part used.  Multiple
             calls may be needed to read or write the larger parts.  When no
             eeprom is present, all words in the returned data are 0xffff.  An
             erased eeprom also reads as all 0xffff.

     UFTDIIOC_WRITE_EEPROM (struct uftdi_eeio)
             Write one or more words to the configuration eeprom.  The
             uftdi_eeio values are as described for UFTDIIOC_READ_EEPROM.

             The FTDI chip does a blind write to the eeprom, and it will
             appear to succeed even when no eeprom is present.  To ensure a
             good write you must read back and verify the data.  It is not
             necessary to erase before writing.  Any position within the
             eeprom can be overwritten at any time.

             Erase the entire eeprom.  This is useful primarily for test and
             debugging, as there is no need to erase before writing.  To help
             prevent accidental erasure caused by calling the wrong ioctl, you
             must pass the special value UFTDI_CONFIRM_ERASE as the argument
             to this ioctl.

     The uftdi driver supports the following adapters:

        B&B Electronics USB->RS422/485 adapter
        Elexol USB MOD1 and USB MOD3
        HP USB-Serial adapter shipped with some HP laptops
        Inland UAS111
        QVS USC-1000
        Buffalo PC-OP-RS / Kurouto-shikou KURO-RS universal remote
        Prologix GPIB-USB Controller

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

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

     tty(4), ucom(4), usb(4)

     The uftdi driver appeared in FreeBSD 4.8 from NetBSD 1.5.

FreeBSD 11.1-RELEASE-p4         April 26, 2017         FreeBSD 11.1-RELEASE-p4
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