Skip to content

CB3S Wi-Fi Module

by Tuya Inc.

Product page

Parameter Value
Board code cb3s
MCU BK7231N
Manufacturer Beken
Series BK72XX
Frequency 120 MHz
Flash size 2 MiB
RAM size 256 KiB
Voltage 3.0V - 3.6V
I/O 14x GPIO, 6x PWM, 2x UART, 1x ADC
Wi-Fi 802.11 b/g/n
Bluetooth BLE v5.1
FCC ID 2ANDL-CB3S

Usage

Board code: cb3s

In platformio.ini:

[env:cb3s]
platform = libretiny
board = cb3s
framework = arduino

In ESPHome YAML:

bk72xx:
  board: cb3s

Pinout

Pinout

Pin functions

Name(s) UART IĀ²C SPI PWM Other
P0 TX2
P6 PWM0
P7 PWM1
P8 PWM2
P9 PWM3
P10 RX1
P11 TX1
P14
P20 SCL1 TCK
P21 SDA1 TMS
P22 TDI
P23, ADC3 TDO
P24 PWM4
P26 PWM5

Flash memory map

Flash size: 2 MiB / 2,097,152 B / 0x200000

Hex values are in bytes.

Name Start Length End
Bootloader 0x000000 68 KiB / 0x11000 0x011000
App Image 0x011000 1.1 MiB / 0x119000 0x12A000
OTA Image 0x12A000 664 KiB / 0xA6000 0x1D0000
Calibration 0x1D0000 4 KiB / 0x1000 0x1D1000
Network Data 0x1D1000 4 KiB / 0x1000 0x1D2000
TLV Store 0x1D2000 4 KiB / 0x1000 0x1D3000
Key-Value Store 0x1D3000 32 KiB / 0x8000 0x1DB000
User Data 0x1DB000 148 KiB / 0x25000 0x200000
Tuya Storage 0x1ED000 76 KiB / 0x13000 0x200000

Bootloader and app partitions contain CRC16 sums every 32 bytes. That results in the actual flash offsets/sizes not aligned to sector boundaries. To simplify calculations, the values shown in the table (extracted from bootloader's partition table) were aligned to 4096 bytes.