The CH34X family comprises widely used USB‑to‑serial chips manufactured by WCH (WinChipHead), commonly integrated into generic UNO R3, ESP8266, and ESP32 development boards.
Overview
- 8 GPIO PINS DOWN TO 2 SIX PINS BACK ON EVERY BUILD: A 4x4 matrix keypad wired directly takes eight GPIO pins. Through the adapter it needs two — SDA and SCL. The six pins you get back stay free for displays, SD cards, servos and sensors, and other I2C devices can share the same two wires.
- RIGID HOUSING, INDIVIDUAL KEYS BUILT FOR REPEATED PRESSES: Molded ABS frame with 16 separately raised keys on a PCB — 0-9, A-D, star and hash. 160-180g actuation force and under 100 ohm contact resistance give a firm, repeatable press rather than a soft membrane feel.
- NO JUMPER WIRES BETWEEN THEM FACTORY PRE-SOLDERED HEADER: The 2.54mm 8-pin header arrives already soldered to the keypad and plugs straight into the adapter socket. Four wires — GND, VCC, SDA, SCL — go to your board. Runs on 3.3V or 5V logic, so no level shifter is needed.
- TWO IN THE PACK ONE TO BUILD WITH, ONE IN RESERVE: Two c... Read More...
2-Pack 4x4 Matrix Keypad with I2C Adapter
$27.71
Projects
HC-05 Bluetooth Module and Arduino Beginner Tutorial
This is a basic example to get you start with HC-05 Bluetooth Module. Depending on your specific requirements and the functionality you want, you may need to expand and modify the sketch accordingly.
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