Module: Piface Digital GPIO

Table of Contents

• PifaceDigital Module Documentation
• Introduction
• Configuration Options
  • Database Configuration Notes
  • XML Config Example

Explain how to use the Piface board as a GPIO backend.

PifaceDigital Module Documentation

Introduction

Documentation for the PifaceDigital module. This provide support for using the PifaceDigital device as a GPIO controller. This can be very handy because it eases wiring.

This module requires that the Linux Kernel Module SPI be enabled. You can do this through raspi-config on Raspbian.

Configuration Options

See below for various configuration options.

Options	Options	Description	Mandatory
use_database		If true, use database-backed configuration.	NO (defaults to false)
gpios		GPIOS definitions	YES
—>	name	A name for the GPIO device	YES
—>	no	The GPIO number of the piface. Range from 0 to 7	YES
—>	direction	Direction of the PIN. in or out	YES
—>	value	Only for out PIN. The default value of the PIN	YES for output pin
—>	hardware_address	Address of the physical pfdigital.	NO (defaults to 0)

Notes:

• If use_database is true, the module will expose its configuration API over websocket (provided that a Websocket module is available). All other XML configuration option are ignored.
• value is a boolean. It's only for output GPIO and represents the default value.
• hardware_address is used when there are multiple pifacedigital connected to the PI. When there is only 1 piface device, its hardware address is 0.

Database Configuration Notes

It is not possible to mix both database configuration and XML configuration. If the XML configuration set use_database to true, then all other XML configuration values are ignored.

When configuration is updated (create/update/delete gpio objects) is not loaded by the module. Restarting Leosac is required to apply new configuration.

XML Config Example

<module>
    <name>PIFACEDIGITAL_GPIO</name>
    <file>libpifacedigital.so</file>
    <level>2</level>
    <module_config>
        <gpios>
            <gpio>
                <name>wiegand_green</name>
                <no>3</no>
                <direction>out</direction>
                <value>false</value>
            </gpio>
            <gpio>
                <name>wiegand_buzzer</name>
                <no>2</no>
                <direction>out</direction>
                <value>false</value>
            </gpio>
            <!-- Prepare GPIO for our Wiegand reader -->
            <gpio>
                <name>wiegand_data_high</name>
                <no>1</no>
                <direction>in</direction>
            </gpio>
            <gpio>
                <name>wiegand_data_low</name>
                <no>0</no>
                <direction>in</direction>
            </gpio>
        </gpios>
    </module_config>
</module>