Alcor6L/eLua/i2c

This module contains functions for accessing the I2C interfaces of the eLua CPU.

Only master I2C mode is implemented in eLua.

=Functions=

i2c.setup
Setup the I2C interface.

speed = i2c.setup( id, speed )


 * id - the ID of the I2C interface.
 * speed - the clock frequency of the I2C interface. It can be i2c.FAST (400KHz), i2c.SLOW (100KHz) or a number giving the required I2C bus clock speed in Hz.

Returns:
 * speed - the actual speed of the I2C interface.

i2c.start
Send a START on the specified I2C interface.

i2c.start( id )


 * id - the ID of the I2C interface.

Returns: nothing.

i2c.stop
Send a STOP on the specified I2C interface.

i2c.stop( id )


 * id - the ID of the I2C interface.

Returns: nothing.

i2c.address
Send an address on the I2C interface.

acked = i2c.address( id, address, direction )


 * id - the ID of the I2C interface.
 * address - the address.
 * direction - i2c.TRANSMITTER if the master wants to send data, or i2c.RECEIVER if the master wants to receive data.

Returns:
 * acked - true if the address was acknowledged by an I2C slave, false otherwise.

i2c.write
Writes data to a slave that has already acknowledged an i2c.address call.

wrote = i2c.write( id, data1, [data2], ..., [datan] )


 * id - the ID of the I2C interface.
 * data1 - the data to send. It can be either a number between 0 and 255, a string or a table (array) of numbers.
 * data2 (optional) - the second data to send.
 * datan (optional) - the n-th data to send.

Returns:
 * wrote - the number of bytes actually written.

i2c.read
data = i2c.read( id, numbytes )

Reads a number of bytes from a slave that has already acknowledged an i2c.address call. It acknowledges all the bytes received except for the last one.


 * id - the ID of the I2C interface.
 * numbytes - the number of bytes to read.

Returns:
 * data - a string with all the data read from the I2C interface.