28 lines
959 B
Python
28 lines
959 B
Python
# SPDX-FileCopyrightText: 2021 Scott Shawcroft, written for Adafruit Industries
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# SPDX-FileCopyrightText: 2022 Jeff Epler, written for Adafruit Industries
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#
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# SPDX-License-Identifier: MIT
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import adafruit_pioasm
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# NeoPixels are 800khz bit streams. Zeroes are 1/3 duty cycle (~416ns) and ones
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# are 2/3 duty cycle (~833ns).
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text_program = """
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.program ws2812
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.side_set 1
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.wrap_target
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bitloop:
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out x 1 side 0 [1]; Side-set still takes place when instruction stalls
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jmp !x do_zero side 1 [1]; Branch on the bit we shifted out. Positive pulse
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do_one:
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jmp bitloop side 1 [1]; Continue driving high, for a long pulse
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do_zero:
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nop side 0 [1]; Or drive low, for a short pulse
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.wrap
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"""
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program = adafruit_pioasm.Program(text_program, build_debuginfo=True)
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program.print_c_program("pio_ws2812", qualifier="static const")
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program = adafruit_pioasm.Program(text_program, build_debuginfo=False)
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program.print_c_program("pio_ws2812_short")
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