avr/rfm69hcw/rfm.c

/*
Copyright 2022, Savanni D'Gerinel <savanni@luminescent-dreams.com>

This file is part of Savanni's AVR library.

Lumeto is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

Lumeto is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with Lumeto. If not, see <https://www.gnu.org/licenses/>.
*/


#include <rfm.h>

void rfm_write(rfm_t *rfm, uint8_t reg, uint8_t *data, size_t length) {
    spi_acquire(&rfm->spi);
    spi_transfer_byte(&rfm->spi, _BV(7) | reg);
    for (size_t i = 0; i < length; i++) {
        spi_transfer_byte(&rfm->spi, data[i]);
    }
    spi_release(&rfm->spi);
}

void rfm_read(rfm_t *rfm, uint8_t reg, uint8_t *data, size_t length) {
    spi_acquire(&rfm->spi);
    spi_transfer_byte(&rfm->spi, reg);
    for (size_t i = 0; i < length; i++) {
        data[i] = spi_transfer_byte(&rfm->spi, 0);
    }
    spi_release(&rfm->spi);
}

void rfm_initialize(rfm_t *rfm) {
    spi_initialize(&rfm->spi);
}

void rfm_packet_format(rfm_t *rfm, packet_format_e format, size_t length) {
    switch (format) {
        case unlimited:
            rfm_write(rfm, 0x37, (uint8_t [1]){ 0 }, 1);
            rfm_write(rfm, 0x38, (uint8_t [1]){ 0 }, 1);
            break;
        case fixed:
            rfm_write(rfm, 0x37, (uint8_t [1]){ 0 }, 1);
            rfm_write(rfm, 0x38, (uint8_t [1]){ length }, 1);
            break;
        case variable:
            rfm_write(rfm, 0x37, (uint8_t [1]){ _BV(7) }, 1);
            rfm_write(rfm, 0x38, (uint8_t [1]){ 0 }, 1);
            break;
    }
}

uint8_t rfm_temperature(rfm_t *rfm) {
    uint8_t ready = 0;
    uint8_t temp;
    rfm_write(rfm, 0x4e, (uint8_t [1]){ _BV(3) }, 1);
    _delay_ms(1);

    uint8_t i = 0;
    while (!(ready & _BV(2)) && i < 10) {
        rfm_read(rfm, 0x4e, &ready, 1);
        i++;
        _delay_us(100);
    }

    rfm_read(rfm, 0x4f, &temp, 1);

    return temp;
}

uint8_t rfm_mode(rfm_t *rfm) {
    uint8_t mode_flag;
    rfm_read(rfm, 0x01, &mode_flag, 1);
    return mode_flag;
}

uint8_t rfm_status(rfm_t *rfm) {
    uint8_t status_flag;
    rfm_read(rfm, 0x28, &status_flag, 1);
    return status_flag;
}

void rfm_listen(rfm_t *rfm) {
    rfm_write(rfm, 0x01, (uint8_t [1]){ _BV(6) }, 1);
    _delay_ms(100);
}

uint32_t rfm_frequency(rfm_t *rfm) {
    uint8_t frequency_bytes[3];
    uint32_t frequency;
    rfm_read(rfm, 0x07, &frequency_bytes[2], 1);
    rfm_read(rfm, 0x08, &frequency_bytes[1], 1);
    rfm_read(rfm, 0x09, &frequency_bytes[0], 1);

    frequency = frequency_bytes[2];
    frequency = frequency << 8;
    frequency += frequency_bytes[1];
    frequency = frequency << 8;
    frequency += frequency_bytes[0];
    return frequency * 61;
}

uint8_t rfm_set_mode(rfm_t *rfm, mode_e mode) {
    uint8_t mode_flags;
    rfm_read(rfm, 0x01, &mode_flags, 1);
    mode_flags = mode_flags & 0b11100011;
    /*
    mode_flags += (mode << 2);
    rfm_write(rfm, 0x01, &mode_flags, 1);
    */
    return mode_flags;
}

uint8_t rfm_irq_1(rfm_t *rfm) {
    uint8_t irq;
    rfm_read(rfm, 0x27, &irq, 1);
    return irq;
}