NiceMCU XH-WB3S

by SparkleIoT - product page

• Info & flashing guide

Information
Board code	xh-wb3s
MCU	Beken BK7238
Series	BK72XX
Partition layout	SDK default (OTA 0x132000, RF 0x1E0000)
Encryption keys	-- no encryption --
Specifications
Frequency	120 MHz
Flash size	2 MiB
RAM size	256 KiB
Voltage	3.0V - 3.6V
I/O	19x GPIO, 6x PWM, 2x UART, 6x ADC
Wi-Fi	802.11 b/g/n
Bluetooth	BLE v5.2

Usage

Board code: xh-wb3s

In platformio.ini:

[env:xh-wb3s]
platform = libretiny
board = xh-wb3s
framework = arduino

In ESPHome YAML:

bk72xx:
  board: xh-wb3s

Quick flashing guide

• ltchiptool user guide
• full flashing guide

Pin	Connection
P10 / RX1	TX of USB-UART adapter
P11 / TX1	RX of USB-UART adapter
CEN (Chip-Enable)	GND to reset the chip

1. Connect the USB-UART adapter.
2. Start the flashing process.
3. Keep shorting CEN to GND or power-cycling the device, until flashing starts.

Pinout

Pin functions

Name(s)	UART	I²C	SPI	PWM	Other
P0	TX2
P1, ADC5	RX2
P6				PWM0	TCK
P7				PWM1	TMS
P8				PWM2	TDI
P9				PWM3	TDO
P10, ADC6	RX1
P11	TX1
P14			SCK
P15		SCL2	CS
P16			MOSI
P17		SDA2	MISO
P20, ADC3
P21
P22
P23
P24, ADC2		SCL2		PWM4
P26, ADC1		SDA2		PWM5
P28, ADC4

Flash memory map

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

Hex values are in bytes.

Name	Code	Start	Length	End
Bootloader	bootloader	0x000000	68 KiB / 0x11000	0x011000
App Image	app	0x011000	1.1 MiB / 0x121000	0x132000
OTA Image	download	0x132000	664 KiB / 0xA6000	0x1D8000
LibreTiny Storage	kvs	0x1D8000	32 KiB / 0x8000	0x1E0000
Calibration	calibration	0x1E0000	4 KiB / 0x1000	0x1E1000
(reserved)	-	0x1E1000	8 KiB / 0x2000	0x1E3000
User Data	userdata	0x1E3000	116 KiB / 0x1D000	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.