Busses

Busses are a collection of analog or logic nets of the same communication protocol. This enables the ability to decode the information being sent over a particular bus in order to help debug what is being sent and received.

Creating and Enabling A Bus

Before creating a bus, the component signals of the bus need to be instantiated. Then those are used as parameters for creating the given bus.

example_create_bus.py

 from lager import Net, NetType, UART

 tx = Net.get('UART.TX',
         type=NetType.Logic,
         setup_function=setup_nets,
         teardown_function=teardown_nets)

 rx = Net.get('UART.RX',
         type=NetType.Logic,
         setup_function=setup_nets,
         teardown_function=teardown_nets)

 uart = UART(tx=tx,rx=rx)
 uart.enable()

Example of Creating A Bus

~  lager bus uart --source-tx UART.TX --source-rx UART.RX --dut 1

Note

Unlike with other nets, e.g. analog or logic, a target net does not need to be specified for busses. You do, however, have to specify one or more source nets that comprise the bus.

Data Formatting and Presentation

Regardless of bus type, decoded data can be presented in either ASCII, HEX, Decimal, or Binary format. The decoded data can be presented to you via the webapp the terminal or a python script.

format_data_ascii.py

 from lager import Net, NetType, UART

 tx = Net.get('UART.TX',
         type=NetType.Logic,
         setup_function=setup_nets,
         teardown_function=teardown_nets)

 rx = Net.get('UART.RX',
         type=NetType.Logic,
         setup_function=setup_nets,
         teardown_function=teardown_nets)

 uart = UART(tx=tx,rx=rx)
 uart.format_ascii()

Format Data As ASCII

~  lager bus format ascii --dut 1

retreive_bus_data.py

 from lager import Net, NetType, UART

 tx = Net.get('UART.TX',
         type=NetType.Logic,
         setup_function=setup_nets,
         teardown_function=teardown_nets)

 rx = Net.get('UART.RX',
         type=NetType.Logic,
         setup_function=setup_nets,
         teardown_function=teardown_nets)

 uart = UART(tx=tx,rx=rx)
 print(uart.bus_data())

 #save data
 uart.save_bus_data("path/to/file.csv")