Button&LED module

background

In the process of learning microcontrollers, the minimum system board is often used, but the minimum system board does not have peripherals. In the past, DuPont wires were always used to connect directly to the independent key component pins for testing, which was very inconvenient. In addition, the teacher in the laboratory asked himself to design a maker education kit, and the development board was presented in the form of separate modules. As a practitioner of EDA design, I plan to make the kits mentioned by the teacher one by one.

Introduction

This is a combination of a button module and an LED module. The button part has a 4x4 matrix button and 5 independent buttons. The independent buttons are distributed up, down, left, right and in the middle for direction selection and confirmation. The LED part has only 8 LEDs. The LED and the 4x4 matrix keyboard share 8 GPIOs. The LED uses a common anode connection, so when using the LED, you need to connect CN1 with a jumper cap to provide power. The cover picture is a sample made before, but the chip resistors and LEDs are 0402. It was extremely difficult for me to solder by hand. I gave up after soldering a set. Now it has been changed to 0603 resistors and 0805 LEDs. The first version is now only For keyboard use. In the first version released before, a kind person reminded me to add diodes to the buttons to prevent ghost buttons, but I still didn't add them. The buttons on the learning development board I used didn't seem to have added them. I was afraid of troublesome patching, so I didn't add them.

Schematic~~~~

PCB

dig a hole

I am going to make a complete set of separate learning and development modules. First, I will make various commonly used basic learning modules one by one. Finally, I will make a development board by myself. There should be two types, one 51 and one stm32, which is convenient for DIY. It can also be left to laboratory study.