Based on the LCSC Taishanpai 3.1-inch smartphone

Functional Description:
Schematic Diagram: Based on the Taishanpai Training Camp's 3.1-inch Smartphone Training Camp activities, hardware and software design was carried out. Hardware design included the removal of the Taishanpai MIPI interface, microphone & speaker, design of onboard backlight control circuit, 3.1-inch touchscreen and 3.1-inch MIPI interface, completing the basic hardware design of the smartphone.
PCB Design Notes: The PCB design was mainly based on Mr. Wu's small phone tutorial. The main concern was controlling the differential pair trace length and
soldering issues: Manual soldering was mainly difficult on the FPC. Initially, several boards couldn't light up the screen, leading to suspicions that the screen itself was faulty. Later, the FPC connectors were soldered using a blower on the back. Finally, physical verification confirmed that no components were damaged; the problem was primarily with the soldering.
Physical demonstration: Video demonstration: https://www.bilibili.com/video/BV1VwTceZENi/?pop_share=1&vd_source=a1bee00019ba812a5a1c6ce2799547b1
Open source code: VII. Mobile Comprehensive Project - Feishu Cloud Document (feishu.cn)
Code reference Wu Gong's demonstration tutorial, hereby special thanks to Wu Gong, from zero to one, although very general, I still completed my first small project.