flipperzero-firmware/lib/infrared/encoder_decoder/nec/infrared_decoder_nec.c

#include "infrared_protocol_nec_i.h"
#include <core/check.h>

InfraredMessage* infrared_decoder_nec_check_ready(void* ctx) {
    return infrared_common_decoder_check_ready(ctx);
}

bool infrared_decoder_nec_interpret(InfraredCommonDecoder* decoder) {
    furi_assert(decoder);

    bool result = false;

    if(decoder->databit_cnt == 32) {
        uint8_t address = decoder->data[0];
        uint8_t address_inverse = decoder->data[1];
        uint8_t command = decoder->data[2];
        uint8_t command_inverse = decoder->data[3];
        uint8_t inverse_command_inverse = (uint8_t)~command_inverse;
        uint8_t inverse_address_inverse = (uint8_t)~address_inverse;
        if((command == inverse_command_inverse) && (address == inverse_address_inverse)) {
            decoder->message.protocol = InfraredProtocolNEC;
            decoder->message.address = address;
            decoder->message.command = command;
            decoder->message.repeat = false;
            result = true;
        } else {
            decoder->message.protocol = InfraredProtocolNECext;
            decoder->message.address = decoder->data[0] | (decoder->data[1] << 8);
            decoder->message.command = decoder->data[2] | (decoder->data[3] << 8);
            decoder->message.repeat = false;
            result = true;
        }
    } else if(decoder->databit_cnt == 42) {
        uint32_t* data1 = (void*)decoder->data;
        uint16_t* data2 = (void*)(data1 + 1);
        uint16_t address = *data1 & 0x1FFF;
        uint16_t address_inverse = (*data1 >> 13) & 0x1FFF;
        uint16_t command = ((*data1 >> 26) & 0x3F) | ((*data2 & 0x3) << 6);
        uint16_t command_inverse = (*data2 >> 2) & 0xFF;

        if((address == (~address_inverse & 0x1FFF)) && (command == (~command_inverse & 0xFF))) {
            decoder->message.protocol = InfraredProtocolNEC42;
            decoder->message.address = address;
            decoder->message.command = command;
            decoder->message.repeat = false;
            result = true;
        } else {
            decoder->message.protocol = InfraredProtocolNEC42ext;
            decoder->message.address = address | (address_inverse << 13);
            decoder->message.command = command | (command_inverse << 8);
            decoder->message.repeat = false;
            result = true;
        }
    }

    return result;
}

// timings start from Space (delay between message and repeat)
InfraredStatus infrared_decoder_nec_decode_repeat(InfraredCommonDecoder* decoder) {
    furi_assert(decoder);

    float preamble_tolerance = decoder->protocol->timings.preamble_tolerance;
    uint32_t bit_tolerance = decoder->protocol->timings.bit_tolerance;
    InfraredStatus status = InfraredStatusError;

    if(decoder->timings_cnt < 4) return InfraredStatusOk;

    if((decoder->timings[0] > INFRARED_NEC_REPEAT_PAUSE_MIN) &&
       (decoder->timings[0] < INFRARED_NEC_REPEAT_PAUSE_MAX) &&
       MATCH_TIMING(decoder->timings[1], INFRARED_NEC_REPEAT_MARK, preamble_tolerance) &&
       MATCH_TIMING(decoder->timings[2], INFRARED_NEC_REPEAT_SPACE, preamble_tolerance) &&
       MATCH_TIMING(decoder->timings[3], decoder->protocol->timings.bit1_mark, bit_tolerance)) {
        status = InfraredStatusReady;
        decoder->timings_cnt = 0;
    } else {
        status = InfraredStatusError;
    }

    return status;
}

void* infrared_decoder_nec_alloc(void) {
    return infrared_common_decoder_alloc(&infrared_protocol_nec);
}

InfraredMessage* infrared_decoder_nec_decode(void* decoder, bool level, uint32_t duration) {
    return infrared_common_decode(decoder, level, duration);
}

void infrared_decoder_nec_free(void* decoder) {
    infrared_common_decoder_free(decoder);
}

void infrared_decoder_nec_reset(void* decoder) {
    infrared_common_decoder_reset(decoder);
}