oakdevtech_icepython.py

# SPDX-FileCopyrightText: 2017 Scott Shawcroft, written for Adafruit Industries
# SPDX-FileCopyrightText: Copyright (c) 2023 Seth Kerr for Oak Development Technologies
#
# SPDX-License-Identifier: MIT
"""
`oakdevtech_icepython`
================================================================================

A library for programming iCE40 FPGA from Lattice Semi


* Author(s): Seth Kerr

Implementation Notes
--------------------

**Hardware:**

.. todo:: Add links to any specific hardware product page(s), or category page(s).
  Use unordered list & hyperlink rST inline format: "* `Link Text <url>`_"

**Software and Dependencies:**

* Adafruit CircuitPython firmware for the supported boards:
  https://circuitpython.org/downloads

.. todo:: Uncomment or remove the Bus Device and/or the Register library dependencies
  based on the library's use of either.

# * Adafruit's Bus Device library: https://github.com/adafruit/Adafruit_CircuitPython_BusDevice
# * Adafruit's Register library: https://github.com/adafruit/Adafruit_CircuitPython_Register
"""

# imports
import time
import io
import digitalio

__version__ = "0.0.0+auto.0"
__repo__ = "https://github.com/skerr92/Oakdevtech_CircuitPython_IcePython.git"


class Oakdevtech_icepython:
    """Driver for programming Lattice Semiconductor iCE40 FPGA over SPI"""

    def __init__(self, spi, chip_sel, reset, filename=None):
        self._spi = spi
        self._filename = filename
        self._reset = digitalio.DigitalInOut(reset)
        self._reset.direction = digitalio.Direction.OUTPUT
        self._chip_sel = digitalio.DigitalInOut(chip_sel)
        self._chip_sel.direction = digitalio.Direction.OUTPUT
        self._reset.value = True
        self._chip_sel.value = True
        try:
            self._file = io.open(filename, mode="rb")  # pylint: disable=R1732
        except:  # pylint: disable=W0133,W0702
            Exception("\nNo such file: ")  # pylint: disable=W0702
        finally:
            print("\nfinished init...")

    def set_bin_file(self, filename) -> None:
        """Change the current binary file to load"""
        self._filename = filename

    def reset_fpga(self) -> None:
        """Reset the FPGA"""
        self._reset.value = False
        time.sleep(0.1)
        self._reset.value = True

    def program_fpga(self) -> None:
        """
        Write the binary to the FPGA.
        If the file has a zero length, print an error.
        Otherwise we continue with programming the FPGA.
        """
        filecontents = self._file.read()
        if len(filecontents) > 0:
            print("in the write of my life!")
            while not self._spi.try_lock():
                pass
            self._spi.configure(baudrate=1000000, phase=1, polarity=1)
            self._reset.value = False
            time.sleep(0.1)
            self._chip_sel.value = False
            self._reset.value = True
            time.sleep(0.1)
            self._chip_sel.value = True
            i = 0
            while i < 8:
                self._spi.write(bytes(0))
                i = i + 1
            self._spi.write(filecontents)
            self._chip_sel.value = True
            i = 0
            while i < 100:
                self._spi.write(bytes(0))
                i = i + 1
            self._chip_sel.value = False
            temp_buf = bytearray(2)
            self._spi.readinto(temp_buf)
            self._spi.unlock()
        else:
            raise Exception(  # pylint: disable=W0719
                "No file contents '%d' size.."  # pylint: disable=C0209
                % (len(filecontents))
            )