JY-9XX multi coin selector coin acceptor programming

 Features

   Intelligent CPU software control, and high accuracy.

  Self-programming without PC, and automatic self-test for problem

  Accept different kinds of coins at the same time. Free to set up pulses' output.

  Prevent not only electric shock but also electromagnetic interference.

  Support multi coins with only 1 signal output.

  Capable of accepting all worldwide Coins and Tokens

HC-05 Bluetooth module Set in AT command mode

HC-05 embedded Bluetooth serial communication module (can be short for module) has two work modes: order-response work mode and automatic connection work mode. And there are three work roles (Master, Slave and Loopback)

Laser/ LED Audio transmitter and Reciever

            

                      This laser/LED transmitter receiver circuit use light from a laser/led  to transmit an receive signal from a distance. This laser transmitter receiver use a laser/led beam as the carrier in the circuit  .This laser transmitter receiver circuit 

Solve USB to TTL converter Windows driver compatibility issues (Yellow Mark Error Code 10 in Device Manager)

Windows 8/8.1/10 are NOT supported in PL-2303HXA and PL-2303X EOL chip versions. If you are facing this issue when you connect your USB to TTL converter you can do the following steps to fix the issue.

Repair HC-05 Bluetooth module

Some days ago  one of my friend unknowingly connected 12V to  HC- 05 bluetooth module!! :(   no doubt as we know module has stopped working no power LED blink everything has gone and he put it in waste bin.

Convert Float in to String in C

There is a very useful function called dtostrf() which will convert Float in to String

The syntax is 

LED current limiting resistor calculation

To calculate resistor value needed for a simple led circuit use ohms law


R=Vcc−VfIf