Sonoff B1 (R2) RGBCCT Bulb
Sonoff B1 (R2)

Available from:

GPIO #Component
GPIO00 Button1
GPIO01 None
GPIO02 None
GPIO03 None
GPIO04 None
GPIO05 None
GPIO09 None
GPIO10 None
GPIO12 MY92x1 DI
GPIO13 None
GPIO15 None
GPIO16 None
Configuration (old format, will be converted to new template when applied)
{"NAME":"Sonoff B1","GPIO":[17,0,0,0,0,0,0,0,143,0,144,0,0],"FLAG":0,"BASE":26,"CMND":"LedTable 0"}

Sonoff B1 R2 is the replacement for Sonoff B1 and can be programmed the same way as the B1. See here for more background information.

Sonoff B1 uses hardware PWM (My92x1 chips) and has hardware Gamma correction. You need to disable software Gamma correction with LedTable 0, as included in the temmplate above.

Serial Flashing

Please see the Hardware Preparation page for general instructions.

As always, you need to access the serial interface. First pop up the top part of the bulb with controlled force. The PCB as shown in the image will become visible.

Sonoff B1 PCB

Sonoff B1 PCB

The four serial pins (3V3, RX, TX, GND) as well as the GPIO0 signal line are available as test points and clearly marked. Solder wires to those or use pogo pins as you prefer.

As with all modules pulling GPIO0 to GND is needed to put the chip in programming mode. You need to connect GPIO0 and GND during power up. An additional GND pad is available in the middle of the PCB.

NOTE: The B1 R2 needs the GPIO0 connected to the GND pad in the middle of the PCB. Otherwise it won’t enter flash mode.

LED HEX10 Color Codes

The Sonoff B1 uses a TEN charter HEX code for all colors. Colors tested with firmware 5.9.1 20171107:

  • 00000000A0 = WARM
  • 000000A000 = COOL
  • 0000A00000 = BLUE
  • FF14500000 = PURPLE
  • 551A8B0000 = DARK PURPLE
  • A300000000 = RED
  • 00ff000000 = GREEN

Official Sources

  • Itead Product Page: http://sonoff.itead.cc/en/products/residential/sonoff-b1
  • Itead Shop: https://www.itead.cc/sonoff-b1.html
  • Itead Wiki: (not available)