40 lines
794 B
Python
40 lines
794 B
Python
"""Count down"""
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import rp2pio
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import adafruit_pioasm
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import array
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program = """
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.program counting_up
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set y, 21 ; set a value in y
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; now send it to be printed
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mov isr, y
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push noblock ; and use PUSH to put it on the receive FIFO
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; Add 1
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mov y, ~ y ; invert it
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jmp y--, fake ; subtract from it
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fake:
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mov isr, ~ y
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push noblock ; and use PUSH to put it on the receive FIFO
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"""
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assembled = adafruit_pioasm.assemble(program)
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## set up a statemachine
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sm = rp2pio.StateMachine(
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assembled,
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frequency=2000,
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)
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buffer = array.array("I", [0])
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# read the data
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sm.readinto(buffer)
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print("Before {0} 0b{0:08b} 0x{0:x}".format(buffer[0]))
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# read the data
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sm.readinto(buffer)
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print("After {0} 0b{0:08b} 0x{0:x}".format(buffer[0]))
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