Interfaces

Interfaces exist on every component and indicate communication methods between components. A component can have multiple interfaces. Each interface must be uniquely named on a component. Each interface is composed of at least one port. Each interface is a source on one component and a sink on another.

For example, the ADC AD4110 could be defined with the following interfaces:

Interface	Direction
Power	Sink
SPI	Sink
Input Discretes	Sink
Output Discretes	Source
Analog Inputs	Sink
Clock	Sink

An FPGA which communicates with the ADC could have the following interfaces:

Interface	Direction
SPI	Source
Input Discretes	Sink
Output Discretes	Source

Naming the interfaces clarifies communication between team members.

Implementation

We will implement a interface using a class.

Code Example

We can define the interfaces for the ADC and the FPGA using DE:

oAdc = de.component.create()
oAdc.add_interface(de.interface('Power'))
oAdc.add_interface(de.interface('SPI'))
oAdc.add_interface(de.interface('Input Discretes'))
oAdc.add_interface(de.interface('Output Discretes'))
oAdc.add_interface(de.interface('Analog Inputs'))
oAdc.add_interface(de.interface('Clock'))

oFPGA = de.component.create()
oSpiInt = oFPGA.create_interface('SPI')
oInDisc = oFPGA.create_interface('Input Discretes')
oOutDisc = oFPGA.create_interface('Output Discretes')

Note

There are two methods to creating an interface. The first method creates the interface and then use the add_interface method of the component class. The second uses the create_interface method of the component class to create the interface. The interface will be returned when using the second method.

If we wanted to grab the SPI interface on the oADC object:

oSpiInterface = oAdc.get_interface_named('SPI')