.. module:: sx1503

**************
SX1503 Module
**************

.. _datasheet: http://www.semtech.com/images/datasheet/sx150x.pdf

This module contains the Zerynth driver for Semtech SX1503 low voltage General Purpose parallel Input/Output.
The unit allows easy serial expansion of I/O through a standard 400kHz I2C interface.
Interrupt handling and programmable logic functions are not implemented (datasheet_).
    
===============
 SX1503 class
===============

.. class:: SX1503(drvname, clk=400000)

    Creates an intance of the SX1503 class.

    :param drvname: I2C Bus used '( I2C0, ... )'
    :param clk: Clock speed, default 400kHz
    
    Example: ::
        
        from semtech.sx1503 import sx1503
        
        ...
        
        port_expander = sx1503.SX1503(I2C1)
        port_expander.pinMode(10,INPUT_PULLUP)
        
        state = port_expander.digitalRead(10)
        
        port_expander.pinMode(0,OUTPUT)
        port_expander.digitalWrite(0,HIGH)
        
        
    
.. method:: pinMode(pin, mode)
    
    Select a mode for a pin.
    Valid *pin* values are from ``0`` to ``15`` included.
    Available modes are:
    
        * ``INPUT``
        * ``INPUT_PULLUP``
        * ``INPUT_PULLDOWN``
        * ``OUTPUT``
    
    
    
.. method:: get_port(port)

    Returns the state of all pins on port *port*.
    As a consequence of having 8 pins for port, returned value can be between ``0`` and ``255``.
    
    ===== ======== =========
    port  I/O bank  pins
    ===== ======== =========
    0     A         0 to 7
    1     B         8 to 15
    ===== ======== =========
    
    
    
.. method:: digitalRead(pin)

    Returns the state of pin *pin*. The state can be ``0`` or ``1``.

    
.. method:: digitalWrite(pin, val)

    Set pin *pin* to value *val*. Value can be ``0`` or ``1``.

    
.. method:: set_port(port, val)
    
    Set all pins on port *port* to value *val*.
    *val* MUST be between ``0`` and ``255``.

    
.. method:: set_boost(mode)

    Set the boost mode (cfr. par 2.2.1 of the datasheet).
    
    ===== ============
    mode   boost mode
    ===== ============
    0       OFF
    1       ON
    ===== ============