pynq.board.button — Python productivity for Zynq (Pynq) v1.0

# Source code for pynq.board.button

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    __author__ = "Giuseppe Natale"
    __copyright__ = "Copyright 2016, Xilinx"
    __email__ = "pynq_support@xilinx.com"

    from pynq import MMIO
    from pynq import PL

    class Button(object):
        """This class controls the onboard push-buttons.

        Attributes
        ----------
        index : int
            Index of the push-buttons, starting from 0.

        """
        _mmio = None

        def __init__(self, index):
            """Create a new Button object.

            Parameters
            ----------
            index : int
                The index of the push-buttons, from 0 to 3.

            """
            if Button._mmio is None:
                Button._mmio = MMIO(int(PL.ip_dict["SEG_btns_gpio_Reg"][0],16))
            self.index = index

        def read(self):
            """Read the current value of the button.

            Returns
            -------
            int
                Either 1 if the button is pressed or 0 otherwise

            """
            curr_val = Button._mmio.read()
            return (curr_val & (1 << self.index)) >> self.index