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.\"
.\" SPDX-License-Identifier: BSD-2-Clause
.\"
.\" Copyright (c) 2024 Denis Bodor <dbodor@rollmops.ninja>
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.Dd February 18, 2024
.Dt I2CTINYUSB 4
.Os
.Sh NAME
.Nm i2ctinyusb
.Nd driver for a USB / I2C bridge device
.Sh SYNOPSIS
To compile this driver into the kernel,
place the following lines in your
kernel configuration file:
.Bd -ragged -offset indent
.Cd "device i2ctinyusb"
.Cd "device usb"
.Cd "device iicbus"
.Ed
.Pp
Alternatively, to load the driver as a
module at boot time, place the following line in
.Xr loader.conf 5 :
.Bd -literal -offset indent
i2ctinyusb_load="YES"
.Ed
.Sh DESCRIPTION
The
.Nm
driver provides support for the device designed by Till Harbaum known
as i2c-tiny-usb. This is initially a very simple circuit built with
an Atmel AVR ATtiny45, but a Raspberry Pi Pico (RP2040) implementation
also exists.
.Pp
The
.Nm
driver creates a
.Xr iicbus 4
child bus to expose the iic functions, enabling I2C sensors, converters
and displays to be connected to any computer with a USB port.
.Pp
More information about this device can be found at:
.Bd -literal -offset indent
https://github.com/harbaum/I2C-Tiny-USB
.Ed
.Pp
and (for the Raspberry Pi Pico version):
.Bd -literal -offset indent
https://github.com/Nicolai-Electronics/rp2040-i2c-interface
.Ed
.Pp
The I2C controller supports read and write transactions with up to 1024
bytes of data, and a write followed by the repeated start followed by a
read transactions up to 1024 bytes.
Zero length transfers are not supported.
.Sh SEE ALSO
.Xr iicbus 4 ,
.Xr usb 4
.Sh HISTORY
The
.Nm
driver and this manual page was written by
.An Denis Bodor Aq Mt dbodor@rollmops.ninja .
|
