HyperWork Luna (HPWDL01) 433 MHz desk lamp remote protocol

HPWDL01.h

/*
 * HPWDL01.h - HyperWork Luna (HPWDL01) 433 MHz desk lamp remote protocol.
 *
 * SPDX-License-Identifier: CC0-1.0
 *
 * Wire protocol reverse-engineered from stock remote captures.
 * Dedicated to the public domain under CC0 1.0: free to copy, modify,
 * reuse and redistribute for any purpose, no attribution required.
 * https://creativecommons.org/publicdomain/zero/1.0/
 *
 * Pure ISO C: no platform or hardware dependencies. Radio setup VALUES
 * live here; applying them to a transceiver and driving the data line
 * stay in the application.
 *
 * Transport: 433.92 MHz OOK carrier at 2.4 kbaud, asynchronous serial
 * data on one GPIO. HIGH = carrier on, LOW = carrier off.
 *
 * Payload: 24-bit code, sent MSB first, OOK pulse-length coded:
 *     code = HPWDL01_PREFIX << 8 | command
 *
 * One frame:
 *     1. HIGH  HPWDL01_LEADER_US     (preamble)
 *     2. LOW   HPWDL01_START_GAP_US  (sync gap)
 *     3. 24 bits, MSB first; each bit = time HIGH, then time LOW:
 *          bit 1 -> HIGH HPWDL01_LONG_US,  LOW HPWDL01_SHORT_US
 *          bit 0 -> HIGH HPWDL01_SHORT_US, LOW HPWDL01_LONG_US
 *     4. the last bit ends HIGH; HPWDL01_GAP_US runs with the line
 *        still HIGH (carrier on), then the next repeated frame starts
 *
 * All timings are microseconds.
 */

#ifndef HPWDL01_H
#define HPWDL01_H

#include <stdint.h>

#ifdef __cplusplus
extern "C" {
#endif

/* Radio transport parameters:
 * 433.92 MHz OOK carrier, 2.4 kbaud asynchronous serial data line. */
#define HPWDL01_RF_FREQ_MHZ        433.92f
#define HPWDL01_TX_DATA_RATE_KBAUD 2.4f
#define HPWDL01_MODULATION         2    /* ASK/OOK */
#define HPWDL01_CC_MODE            0    /* infinite packet mode */
#define HPWDL01_PKT_FORMAT         3    /* asynchronous serial mode */
#define HPWDL01_IOCFG0_GDO0_TX     0x0D /* data pin = async serial TX stream */

/* Bit / frame timing (us) */
#define HPWDL01_SHORT_US     430
#define HPWDL01_LONG_US      1280
#define HPWDL01_LEADER_US    1100
#define HPWDL01_START_GAP_US 12000
#define HPWDL01_GAP_US       12080

/* 24-bit payload: HPWDL01_PREFIX << 8 | command */
#define HPWDL01_PREFIX 0x1397UL

/* Command table (X-macro): HPWDL01_X(name, commandByte).
 * The stock remote also knows COLOR_ALT (0x55), same effect as COLOR. */
#define HPWDL01_COMMAND_TABLE(X) \
    X(COLOR,           0xAA) \
    X(COLOR_ALT,       0x55) \
    X(BRIGHTNESS_UP,   0xAD) \
    X(BRIGHTNESS_DOWN, 0x05) \
    X(OFF,             0xFF)

/* 8-bit command bytes. */
enum {
#define HPWDL01_X(name, byte) HPWDL01_CMD_##name = (byte),
    HPWDL01_COMMAND_TABLE(HPWDL01_X)
#undef HPWDL01_X
};

/* Actual 24-bit wire codes: HPWDL01_PREFIX << 8 | command byte. */
enum {
#define HPWDL01_X(name, byte) \
    HPWDL01_CODE_##name = ((uint32_t)HPWDL01_PREFIX << 8) | (uint32_t)(byte),
    HPWDL01_COMMAND_TABLE(HPWDL01_X)
#undef HPWDL01_X
};

/* Frames per burst for each action */
#define HPWDL01_COLOR_REPEATS           2
#define HPWDL01_BRIGHTNESS_BASE_REPEATS 1
#define HPWDL01_OFF_REPEATS             22
#define HPWDL01_BRIGHTNESS_MAX_LEVEL    10

/* One payload bit on the wire: time HIGH, then time LOW. */
typedef struct {
    uint16_t highUs;
    uint16_t lowUs;
} HPWDL01_BitPulse;

static inline HPWDL01_BitPulse HPWDL01_bitPulse(uint8_t bit)
{
    /* Row 0 = bit 0, row 1 = bit 1. */
    static const HPWDL01_BitPulse PULSES[2] = {
        {HPWDL01_SHORT_US, HPWDL01_LONG_US},
        {HPWDL01_LONG_US,  HPWDL01_SHORT_US}
    };
    return PULSES[bit != 0];
}

#ifdef __cplusplus
}
#endif

#endif /* HPWDL01_H */