PL and Bitstream classes

The PL is mainly an internal class used by the Overlay class. The PL class launches a PL server which manages the loaded overlay. The PL server can stop multiple overlays from different applications from overwriting the currently loaded overlay.

The overlay Tcl file is parsed by the PL class to generate the IP, clock, interrupts, and gpio dictionaries (lists of information about IP, clocks and signals in the overlay).

The Bitstream class can be found in the source file, and can be used instead of the overlay class to download a bitstream file to the PL without requiring an overlay Tcl file. This can be used for for testing, but these attributes can also be accessed through the Overlay class (which inherits from this class). Using the Overlay class is the recommended way to access these attributes.



PL.timestamp # Get the timestamp when the current overlay was loaded

PL.ip_dict # List IP in the overlay

PL.gpio_dict # List GPIO in the overlay

PL.interrupt_controllers # List interrupt controllers in the overlay

PL.interrupt_pins # List interrupt pins in the overlay

PL.hierarchy_dict # List the hierarchies in the overlay


from pynq import Bitstream

bit = Bitstream("base.bit") # No overlay Tcl file required



More information about the PL module can be found in the Module sections