【RA MCU】Mechanical small keyboard

Project Introduction:
This mechanical keyboard is based on the Renesas RA2E1 main control chip. It uses the Qinheng CH9329 to communicate with the PC via USB HID. It also integrates the SL2.1A chip to provide two additional USB interfaces. It also has an integrated UART interface that can be used to burn firmware and view debugging information. It also has an external SW burning interface.


Project function introductionHardware
partThe
hardware design idea is to use SL2.1A chip to connect to PC, two of which are connected to the main control burning serial port and CH9329 chip respectively, to realize a USB interface that supports keyboard input and serial port burning functions at the same time, and at the same time, 2 USB interfaces can be used to connect non-full-size keyboards and peripherals such as U disks (low-power peripherals)
The keyboard matrix uses row scanning to capture the key status. Since the input status of the Renesas RA2E1 chip pin does not support internal pull-down, a pull-down resistor is added to the column pinThe
key backlight does not support IC control, and it is recommended to choose a current limiting resistor R10 of about 1K. I tried 500R. The CH9329 chip will cause insufficient power supply when sending dataSoftware
partSoftware
open source address: https://gitee.com/walkline/ramcu-mechanical-keypadThe
software development uses the officially recommended E2 Studio, which can install various components and the compilation environment in one click. It is indeed more user-friendlyThe
three-dimensional structure part is
relatively compact, so only one M3 fixing hole is arranged, that is, the screw hole in the lower left corner of the figure can be used to fix the PCB, and the other two and USB-A The opening plays a supporting role.
Attachment description
3DShell_Mechanical Keypad_PCB_B.stl: 3D shell file
ramcu-mechanical-keypad.hex: Release version of the main control firmware file
PCB_Mechanical Keypad_PCB_ibom.rar: Visual BOM table