.\" man page for Munts Technologies Linux Simple I/O Library
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.TH libi2c 2 "21 December 2018" "version 1" "Linux Simple I/O Library"
.SH NAME
.B libi2c
\-\- Linux Simple I/O Library: I\u\s-22\s+2\dC Module
.SH SYNOPSIS
.nf
.B #include <libsimpleio/libi2c.h>

.BI "void I2C_open(const char *" name ", int32_t *" fd ", int32_t *" error ");"

.BI "void I2C_close(int32_t " fd ", int32_t *" error ");"

.BI "void I2C_transaction(int32_t " fd ", int32_t " slaveaddr ", void *" cmd ", int32_t " cmdlen ","
.BI "  void *" resp ", int32_t " resplen ", int32_t *" error ");"

.fi
Link with
.BR -lsimpleio .
.SH DESCRIPTION
.nh
All functions return either
.B 0
(upon success) or an
.B errno
value (upon failure) in
.IR *error .
.PP
.B I2C_open()
opens an I\u\s-22\s+2\dC bus controller device.  The device name,
.BR /dev/i2c-x ,
must be passed in the
.IR name
parameter. Upon success, a file descriptor for the
I\u\s-22\s+2\dC bus controller device is returned in
.IR *fd .
.PP
.B I2C_close()
closes a previously opened I\u\s-22\s+2\dC bus controller device.
.PP
.B I2C_transaction()
performs a single I\u\s-22\s+2\dC bus transaction, with optional transmit and receive
phases.  The I\u\s-22\s+2\dC slave device address must be passed in the
.I slaveaddr
parameter.  Either the address of a command message and its length must be passed in the
.IR cmd " and " cmdlen
parameters, or
.BR NULL " and " 0
for a receive only transaction.  Either the address of a receive buffer and its size must be passed in the
.IR resp " and " resplen
parameters, or
.BR NULL " and " 0
for a transmit only transaction.
.SH SEE ALSO
.BR libsimpleio "(2), " libadc "(2), " libdac "(2), " libevent "(2), " libgpio "(2),"
.br
.BR libhidraw "(2), " libipv4 "(2), " liblinux "(2), " liblinx "(2), " libpwm "(2),"
.br
.BR libserial "(2), " libspi "(2), " libstream "(2), " libwatchdog "(2)"
.SH AUTHOR
Philip Munts dba Munts Technologies.