35 lines
991 B
Plaintext
35 lines
991 B
Plaintext
;
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; Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
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;
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; SPDX-License-Identifier: BSD-3-Clause
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;
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.program hello
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; Repeatedly get one word of data from the TX FIFO, stalling when the FIFO is
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; empty. Write the least significant bit to the OUT pin group.
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loop:
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pull
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out pins, 1
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jmp loop
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% c-sdk {
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static inline void hello_program_init(PIO pio, uint sm, uint offset, uint pin) {
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pio_sm_config c = hello_program_get_default_config(offset);
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// Map the state machine's OUT pin group to one pin, namely the `pin`
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// parameter to this function.
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sm_config_set_out_pins(&c, pin, 1);
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// Set this pin's GPIO function (connect PIO to the pad)
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pio_gpio_init(pio, pin);
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// Set the pin direction to output at the PIO
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pio_sm_set_consecutive_pindirs(pio, sm, pin, 1, true);
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// Load our configuration, and jump to the start of the program
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pio_sm_init(pio, sm, offset, &c);
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// Set the state machine running
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pio_sm_set_enabled(pio, sm, true);
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}
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%}
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