I saw this open-source project on GitHub: https://github.com/SasaKaranovic/DIY-Heart-Keychain.
utilizing capacitive touch technology.
This is a development board based on the Arteri AT32F421 core. It integrates SPI FLASH, three user LEDs, a reset circuit, a USB-to-TTL converter, and all pins are brought out. I have tested it and it works.
This is a development board based on the Arteri AT32F421 core. It integrates SPI FLASH, three user LEDs, a reset circuit, a USB-to-TTL converter, and all pins are brought out. I have tested it and it works.
![a166ebb8e662f13e766f3c79780d4d6.jpg]
![4eceb3391e367f8e5debfac939e1f7b.jpg]
Write card (SanDisk)
![17827c491820e2febc5a43feeb9c436.png]
Read card (SanDisk)
![Read.png]
Plug into expansion dock
![588b3f3c24c710ab19a8b553dfa40ee.jpg]
Plug into expansion dock to read (Patriot)
![509d7ce601a6db20d151845b340e3e1.png]
Plug into expansion dock to write (Patriot)
![0adf522cafb65ee2f19e929c7f9485a.png]
Different cards will affect the speed, but the overall speed remains the same.
Below are the file transfer speeds when all four ports are fully connected
: * USB drive to computer
* ![WeChat image_20231030195700.png]
* Computer to USB drive
* ![WeChat image_20231030195704.png]
* USB drive to USB drive
* ![WeChat image_20231030195656.png]
PCB Top Board.zip
PDF_USB2.0 Dock.zip
Altium_USB2.0 Dock.zip
PADS_USB2.0 Dock.zip
BOM_USB2.0 Dock.xlsx
96449
TP4056 charging module
A charging module based on TP4056 (verified)
The TP4056 charging management chip is a commonly used constant current/constant voltage linear charging management chip for single-cell lithium batteries. Due to its internal PMOSFET architecture and reverse charging protection circuit, it does not require an external isolation diode. The module features five current selection levels and an independent switch; a red light illuminates during charging, and a green light illuminates when fully charged. For those with advanced technical skills, thermal feedback can be added for automatic adjustment of the charging current.
The charging current is determined by the Rprog resistor; the specific charging current setting formula is as follows:
PDF_TP4056 charging module.zip
Altium_TP4056 charging module.zip
PADS_TP4056 charging module.zip
BOM_TP4056 charging module.xlsx
96450
LM2596S_ADJ Adjustable Power Module
An adjustable step-down converter based on the LM2596S_ADJ chip, theoretically adjustable from 1.2V to Vin. (Verified)
An adjustable step-down converter based on the LM2596S_ADJ chip, theoretically adjustable from 1.2V to Vin.
Actual measurements show
adjustable voltage from 1.23V to 4.57V at 5V
and from 1.24V to 11.36V at 12V.
PDF_LM2596S_ADJ Adjustable Power Module.zip
Altium_LM2596S_ADJ Adjustable Power Module.zip
PADS_LM2596S_ADJ Adjustable Power Module.zip
BOM_LM2596S_ADJ Adjustable Power Module.xlsx
96451
CH340C Programmer
A programmer based on CH340C that requires no external crystal oscillator and no additional 3V3 power supply (verified).
Tested and confirmed to work with STM32, STC51, Arduino, and ESP32 development boards, with one-click automatic download.
PS: Not yet tested because I don't have a GD32. The two resistors on the CC pin of the Type-C port don't need to be soldered.
In practice, the CH340C chip's built-in 3V3V is sufficient for downloading; no additional LDO power supply is needed (a 100nF decoupling capacitor is recommended).
With the shorting cap on the left, it's 5V; with the cap on the right, it's 3.3V.
Version 0.9 has issues; leaving this as a warning to myself.
PDF_CH340C Programmer.zip
Altium_CH340C programmer.zip
PADS_CH340C Programmer.zip
BOM_CH340C Programmer.xlsx
96452
STM32F103C8T6 Minimum System (Onboard DAPLink)
STM32F103CXT6 Minimum System (Onboard DAPLink)
![cd621dd21e990392e9efdfc54ff06a7.jpg]
JLCPCB official DAPLink [link](https://oshwhub.com/lengyuefeng/a7c57e6d86bd47789178df3fda9219dc), official Gitee programming tutorial [link](https://gitee.com/lcsc/lspiclink), Hex file in appendix.
* Boot0 is pulled low by default; pressing the button pulls it high.
* Onboard DAPLink, using USB-Type-C cable for programming and virtual serial communication.
![0b20353ef777a778cde23a2ce7cb87a.jpg]
![cd621dd21e990392e9efdfc54ff06a7.jpg]
CH55x_DAPLink.hex
PDF_STM32F103C8T6 Minimum System (Onboard DAPLink).zip
Altium_STM32F103C8T6 Minimum System (Onboard DAPLink).zip
PADS_STM32F103C8T6 Minimum System (Onboard DAPLink).zip
BOM_STM32F103C8T6 Minimum System (Onboard DAPLink).xlsx
96453
pixl.js - 1.3-inch OLED version
Based on the open-source documentation, I have removed unnecessary components and screen type information, retaining only the essential components for a 1.3-inch OLED screen.
This is a modified version based on open-source documentation. I've removed unnecessary components and adjusted screen types, retaining only the essential components for a 1.3-inch OLED screen. The original external high-frequency coil has been replaced with an onboard coil. All components have been tested and are working correctly. Alternatively, you can use the external coil as prompted within the project. The firmware is 2.9.1. The latest firmware has issues and won't be included here. The panel files are within the project file, and the 3D printed shell files are in the group files. You can join the group to get them: 573274730
pixljs_all.hex
PDF_pixl.js-1.3-inch OLED version.zip
Altium_pixl.js-1.3-inch OLED version.zip
PADS_pixl.js-1.3-inch OLED version.zip
BOM_pixl.js-1.3-inch OLED version.xlsx
96454
electronic
The required components are a 
京公网安备 11010802033920号
M38225E3XXXHP
