daikin-ir-encoder 0.1.0

Synthesize Daikin AC IR frames from scratch (3-frame and 1-frame transports)

daikin-ir-encoder

Synthesizes Daikin air-conditioner IR command frames and returns raw mark/space timings (microseconds, positive = mark, negative = space) playable by any 38 kHz IR transmitter: Broadlink, XIAO IR Mate

Reverse-engineered from two Daikin remotes (ARC466A9 and ARC480A11). Both remotes use the same 19-byte state frame and sum-mod-256 checksum; they differ only in the IR transport that carries the frame (3-frame vs 1-frame). Some AC can accepts either.

Install

pip install daikin-ir-encoder

No runtime dependencies. Pure Python, 3.11–3.14 tested.

Quick start

from daikin_ir_encoder import build, VARIANT_3FRAME

timings = build(
    power=True,
    mode="cool",          # auto | dry | cool | heat | fan
    temp=21,              # °C; ignored in dry/fan
    fan="auto",           # 1..5 | auto | night | comfort
    v_swing=False,
    h_swing=False,
    econo=False,
    outdoor_quiet=False,  # outdoor-unit quiet mode (not indoor fan)
    intelligent_eye=False,
    powerful=False,       # turbo; AC clears after 20 min
    variant=VARIANT_3FRAME,
)

To schedule the AC to switch on or off at a specific time of day, pass on_timer / off_timer as datetime.time values:

from datetime import time
timings = build(mode="cool", temp=21,
                on_timer=time(7, 30),     # turn ON at 07:30
                off_timer=time(22, 0))    # turn OFF at 22:00

Hand the list to whatever transmitter you have. With an ESPHome remote_transmitter:

- remote_transmitter.transmit_raw:
    carrier_frequency: 38kHz
    code: [3500, -1700, 454, -413, 454, -1280, ...]

With the Home Assistant infrared integration, pass it as Command.timings with modulation=38000. Broadlink and LIRC accept the same raw timing list.

Constants exposed

from daikin_ir_encoder import (
    CARRIER_HZ,           # 38000
    VARIANT_3FRAME,       # "3frame"
    VARIANT_1FRAME,       # "1frame"
    VARIANTS,             # tuple of the above
    MODES,                # {"auto": 0x0, "dry": 0x2, "cool": 0x3, "heat": 0x4, "fan": 0x6}
    MODE_AUTO, MODE_DRY, MODE_COOL, MODE_HEAT, MODE_FAN,
    FAN_SPEEDS,           # {"1": 0x3, ..., "5": 0x7, "auto": 0xA, "night": 0xB, "comfort": 0xA}
    TEMP_RANGES,          # {"cool": (18, 32), "heat": (10, 30), "auto": (18, 30)}
)

TEMP_RANGES is informational — the encoder doesn't clamp. Out-of-range temps raise ValueError (temp × 2 overflows the byte).

Protocol

Carrier	38 kHz
Encoding	PPM, LSB-first; ~454 µs mark; ~413 µs space = 0; ~1280 µs space = 1
Frame	19 bytes — header 11 da 27 00 00, payload, checksum sum(bytes[:18]) & 0xFF
Statefulness	Absolute. Every press carries the full state (mode/temp/fan/swing/power/features). Not a toggle.
3-frame transport	preamble + identity frame + clock frame + state frame; 584 edges, ~450 ms on air.
1-frame transport	preamble + state frame only; 320 edges, ~220 ms on air.

If you don't know which remote your unit shipped with, the AC accepts either — try VARIANT_3FRAME first.

State-frame layout:

Byte	Bits	Field	Notes
0–4	all	Header	constant 11 da 27 00 00
5	0	Power
5	1	ON-timer enable
5	2	OFF-timer enable
5	3	Variant ID	1 for ARC466A9 (3-frame), 0 for ARC480A11 (1-frame)
5	4–7	Mode	0=auto, 2=dry, 3=cool, 4=heat, 6=fan
6	all	Temperature	°C × 2; 0xC0 in dry mode
8	4–7	Fan	3–7 = L1–L5; 0xA = auto/comfort; 0xB = night
8	0–3	V-swing	0xF on, 0x0 off
9	0–3	H-swing	0xF on, 0x0 off
10	all	ON-timer, low 8 bits	minutes-since-midnight
11	0–3	ON-timer, high 4 bits	(11-bit minutes total)
11	4–7	OFF-timer, low 4 bits
12	all	OFF-timer, high 8 bits	(11-bit minutes total)
13	0	Powerful
13	5	Outdoor quiet
16	1	Intelligent Eye
16	2	Econo
16	7	Weekly-timer disable	1 = weekly schedule inactive, 0 = weekly active. 3-frame only — 1-frame has no clock so no weekly. Set via the weekly_active argument; the schedule itself is programmed via a separate command not handled by this library.
18	all	Checksum	sum(bytes[:18]) & 0xFF

Timer fields hold 11-bit minutes. The AC interprets them as time-of-day on devices shipped with ARC466A9 (it has a clock — sentinel 0x600 for "disabled") and as a countdown duration on devices shipped with ARC480A11 (no clock — sentinel 0x000). The on_timer/off_timer arguments take a datetime.time either way; the encoder picks the right sentinel. Caller decides what time(7, 30) means on 1-frame (literal time vs "fire in 7h30m").

Clock (3-frame transport only)

The second frame in the 3-frame transport carries the remote's wall clock:

Byte	Bits	Field	Encoding
0–4	all	Header	constant 11 da 27 00 42
5	all	Minutes since midnight, low 8 bits
6	0–2	Minutes since midnight, high 3 bits	11-bit total, 0–1439
6	3–7	Day of week	1=Sun, 2=Mon, 3=Tue, 4=Wed, 5=Thu, 6=Fri, 7=Sat
7	all	Checksum	sum(bytes[:7]) & 0xFF

from datetime import datetime
from daikin_ir_encoder import build

timings = build(mode="cool", temp=21, dt=datetime.now())

dt defaults to datetime.now(). Pass an explicit datetime for deterministic output. The AC ignores the clock for normal commands — only timer features depend on it.

Mutual-exclusion rules

The encoder mirrors the rules the AC enforces, so the byte stream stays self-consistent:

• powerful=True forces econo, outdoor_quiet, and comfort off and downgrades fan="comfort" to fan="auto" (the real remote reverts to the user's last manual fan; we can't reproduce that without state, so auto is the safest stand-in). intelligent_eye is preserved — verified by capture. The AC itself clears the powerful bit after ~20 minutes; retransmit if you want the new state.
• fan="comfort" is signaled in the identity frame (3-frame transport only). The state frame can't distinguish it from fan="auto" + V-swing off. Combining v_swing=True with fan="comfort" is a contradiction — pick one.
• Outdoor quiet is silently ignored by the AC in dry and fan modes (the bit still goes on the wire).

Tested against

• Daikin FTXS35/42/50 K2V1B split units (R410A)
• Remotes ARC466A9 (3-frame) and ARC480A11 (1-frame)
• ESPHome 2026.5.2 on an XIAO IR Mate (ESP32-C3) as the transmitter

Run the suite with uv run pytest.

Related work

• blafois/Daikin-IR-Reverse

Further refinements over the blafois doc:

• byte 5 timer-enable bits are swapped — bit 1 is the ON-timer enable, bit 2 is the OFF-timer enable
• byte 16 bit 7 is Weekly-timer disable bit
• frame 2 of the 3-frame transport is documented as a fixed 11 da 27 00 42 00 00 54 constant; in our captures it carries the remote's wall clock (day-of-week + minutes-since-midnight + its own checksum). See the Clock section above.

License

Apache-2.0. See LICENSE.

This library is an independent reverse-engineering effort and is not affiliated with or endorsed by Daikin Industries, Ltd. "Daikin" is a trademark of its respective owner; the name is used here solely to describe interoperability.