Add Senville F-mode codebook (RG66A2/BGEFU1) - device_code 8861

[jesse-projects]

Summary

Adds a new SmartIR device code 8861 for Senville Aura mini-split air conditioners using the RG66A2/BGEFU1 remote, captured in Fahrenheit display mode.

Why a second Senville code?

The existing code 2860 was captured in Celsius and bakes the °C display flag into every IR payload — when fired, the indoor LCD reverts to Celsius regardless of user preference. This is problematic for US/Canada users whose AC's physical remote defaults to °F. 8861 provides native Fahrenheit display + complete mode coverage.

Coverage

	2860 (existing)	8861 (this PR)
Display unit	°C (Celsius, forces unit to C)	°F (Fahrenheit, native)
Operation modes	cool, heat, dry	cool, heat, dry, auto, fan_only
Fan modes	auto, quiet, level1, level2, level3	auto, low, med, high (match RG66A2 4-speed)
Temp range	17-30°C, 1°C precision	62-86°F, 1°F precision
Off command	✓	✓
Supported models	SENA/12HF/IZ	SENA/09HF/I, SENA/12HF/I, SENA/18HF/I, SENA/24HF/I

Methodology

• 36 reference captures from a real Senville Aura unit across all modes/fan-speeds/temps + auxiliary buttons
• Midea protocol reverse-engineered from these captures:
  • 48-bit payload + 2-bit gap + 48-bit bitwise-inverse-frame + 1-bit terminator
  • Byte 1: 3-bit mode field (bits 5-7), 3-bit fan field (bits 2-4), sleep flag (bit 1), constant (bit 0)
  • Byte 2: bit-reversed temperature counter in upper nibble, range flag in lower nibble (0x06 for 62-77°F, 0x0E for 78-86°F); constant 0x7E in fan_only mode
  • Byte 5: (sum(byte0..byte4) mod 256) XOR 0xFC (additive checksum with fixed mask)
• 195 missing combos synthesized via formula
• 13 cross-product diff captures verified the synthesis byte-for-byte (100% pass rate)
• 53+ total reference frames matched against derived formulas

Total codes

500 (33 direct captures + 221 synthesized + 246 deterministic duplicates for lock-mode coverage). DRY and AUTO modes have all 4 fan keys present (each pointing to the same auto-fan code per temp) so SmartIR never KeyErrors on fan changes in those modes.

About the code number

I chose 8861 because:

• 2860 = existing upstream Senville Celsius code (complemented, not replaced)
• 8861 sits clearly outside the 1000-3000 mainstream range, in the sparse 8000+ community-custom cluster (alongside existing 8700, 8720, 8800)
• No collision with anything in the current codes/climate/ directory

Happy to renumber if you'd prefer a different value.

Testing

Tested against a 9000 BTU Senville Aura Indoor Unit (SENA/09HF/IZ), firmware 4.0.4 via Broadlink RM4 Pro. All 5 HVAC modes, all 4 fan speeds where applicable, all 25 temps, plus off command verified working end-to-end.

Related work

• Full protocol reverse-engineering writeup, capture toolkit, synthesis pipeline, and HA configuration examples: jesse-projects/senville-ir-toolkit
• Methodology generalizable to other Midea-family rebadges (Pioneer, MrCool, etc.) — the toolkit's capture.py + synthesize.py + verify_synthesis.py workflow can derive new codebooks for any Midea-family remote with similar bit structure

Compatibility

8861 does not replace 2860; both can coexist. Users with the older display preference can continue using 2860; users wanting native °F should switch to 8861.