/** * Copyright (c) 2021 mjcross * * SPDX-License-Identifier: BSD-3-Clause */ #include #include "pico/stdlib.h" #include "nec_transmit.h" // include the library headers #include "nec_receive.h" // Infrared loopback example ('NEC' format) // // Need to connect an IR LED to GPIO 14 via a suitable series resistor (e.g. 1.5k) // and an active-low IR detector to GPIO 15 (e.g. VS1838b) // // Output is sent to stdout int main() { stdio_init_all(); PIO pio = pio0; // choose which PIO block to use (RP2040 has two: pio0 and pio1) uint tx_gpio = 14; // choose which GPIO pin is connected to the IR LED uint rx_gpio = 15; // choose which GPIO pin is connected to the IR detector // configure and enable the state machines int tx_sm = nec_tx_init(pio, tx_gpio); // uses two state machines, 16 instructions and one IRQ int rx_sm = nec_rx_init(pio, rx_gpio); // uses one state machine and 9 instructions if (tx_sm == -1 || rx_sm == -1) { printf("could not configure PIO\n"); return -1; } // transmit and receive frames uint8_t tx_address = 0x00, tx_data = 0x00, rx_address, rx_data; while (true) { // create a 32-bit frame and add it to the transmit FIFO uint32_t tx_frame = nec_encode_frame(tx_address, tx_data); pio_sm_put(pio, tx_sm, tx_frame); printf("\nsent: %02x, %02x", tx_address, tx_data); // allow time for the frame to be transmitted (optional) sleep_ms(100); // display any frames in the receive FIFO while (!pio_sm_is_rx_fifo_empty(pio, rx_sm)) { uint32_t rx_frame = pio_sm_get(pio, rx_sm); if (nec_decode_frame(rx_frame, &rx_address, &rx_data)) { printf("\treceived: %02x, %02x", rx_address, rx_data); } else { printf("\treceived: %08x", rx_frame); } } sleep_ms(900); tx_data += 1; } }