Sipeed Longan Nano - RISC-V GD32VF103CBT6 Development Board

Official board

https://www.gigadevice.com/microcontroller/gd32vf103c8t6/

Specifications
Speed and Memory	
Maximum Speed	Up to 108MHz
Flash Memory	64K
RAM	20K
PSRAM	-
Connectivity	 	 	 
USART	3	LCD	-
UART	-	LCD TFT	-
I2C	2	Camera	-
SPI	3	Ethernet	-
CAN	2	Crypto	-
USB	OTG	SDRAM	-
I2S	2	TMU	-
SDIO	-	SHRTM	-
Analog Interface	
12bit ADC Units	2
12bit ADC Channels	10
12bit DAC Units	2
Packages	
LQFP48

Unknown board AKA Nano LITE

https://www.gigadevice.com/microcontroller/gd32vf103cbt6/

Specifications
Speed and Memory	
Maximum Speed	Up to 108MHz
Flash Memory	128K
RAM	32K
PSRAM	-
Connectivity	 	 	 
USART	3	LCD	-
UART	-	LCD TFT	-
I2C	2	Camera	-
SPI	3	Ethernet	-
CAN	2	Crypto	-
USB	OTG	SDRAM	-
I2S	2	TMU	-
SDIO	-	SHRTM	-
Analog Interface	
12bit ADC Units	2
12bit ADC Channels	10
12bit DAC Units	2
Packages	
LQFP48

TODO

DFU MODE

1. press boot
2. press reset
3. release reset
4. release boot

BOOT + RESET

dmesg

[3539370.249607] usb 1-1.2: new full-speed USB device number 45 using dwc_otg
[3539370.395610] usb 1-1.2: New USB device found, idVendor=28e9, idProduct=0189, bcdDevice= 1.00
[3539370.395626] usb 1-1.2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[3539370.395638] usb 1-1.2: SerialNumber: 䌳䩂

Found DFU: [28e9:0189] ver=0100, devnum=45, cfg=1, intf=0, path="1-1.2", alt=0, name="@Internal Flash  /0x08000000/128*001Kg", serial="??"
dfu-util 0.9

OLD:

Copyright 2005-2009 Weston Schmidt, Harald Welte and OpenMoko Inc.
Copyright 2010-2016 Tormod Volden and Stefan Schmidt
This program is Free Software and has ABSOLUTELY NO WARRANTY
Please report bugs to http://sourceforge.net/p/dfu-util/tickets/




dfu-util

git clone https://git.code.sf.net/p/dfu-util/dfu-util dfu-util

NEW:
Copyright 2005-2009 Weston Schmidt, Harald Welte and OpenMoko Inc.
Copyright 2010-2020 Tormod Volden and Stefan Schmidt
This program is Free Software and has ABSOLUTELY NO WARRANTY
Please report bugs to http://sourceforge.net/p/dfu-util/tickets/

Found DFU: [28e9:0189] ver=0100, devnum=45, cfg=1, intf=0, path="1-1.2", alt=0, name="@Internal Flash  /0x08000000/128*001Kg", serial="3CBJ"

MCU datasheet