/** * Copyright (c) 2020 Raspberry Pi (Trading) Ltd. * * SPDX-License-Identifier: BSD-3-Clause */ #include #include "pico/stdlib.h" #include "hardware/pio.h" #include "differential_manchester.pio.h" // Differential serial transmit/receive example // Need to connect a wire from GPIO2 -> GPIO3 const uint pin_tx = 2; const uint pin_rx = 3; int main() { stdio_init_all(); PIO pio = pio0; uint sm_tx = 0; uint sm_rx = 1; uint offset_tx = pio_add_program(pio, &differential_manchester_tx_program); uint offset_rx = pio_add_program(pio, &differential_manchester_rx_program); printf("Transmit program loaded at %d\n", offset_tx); printf("Receive program loaded at %d\n", offset_rx); // Configure state machines, set bit rate at 5 Mbps differential_manchester_tx_program_init(pio, sm_tx, offset_tx, pin_tx, 125.f / (16 * 5)); differential_manchester_rx_program_init(pio, sm_rx, offset_rx, pin_rx, 125.f / (16 * 5)); pio_sm_set_enabled(pio, sm_tx, false); pio_sm_put_blocking(pio, sm_tx, 0); pio_sm_put_blocking(pio, sm_tx, 0x0ff0a55a); pio_sm_put_blocking(pio, sm_tx, 0x12345678); pio_sm_set_enabled(pio, sm_tx, true); for (int i = 0; i < 3; ++i) printf("%08x\n", pio_sm_get_blocking(pio, sm_rx)); }