TREE

The AT89C51 from ATMEL is the most commonly used variation of the 8051 microcontroller because of the built-in Flash which makes programming / burning very easy. The 8051 has a total of 4 ports for input / output operations which means you can transfer data in or out of the microcontroller through these ports. Let's have a brief introduction to these ports. UPDATE: You can also click this link for an updated version of this post. READ MORE

This circuit is a simple test of USB ports, it is a circuit very useful for anyone working in the field of computer science. To be "stuck" in the PC USB port or an information display Notebook USB device not recognized, just after the yellow LED flashes 3 times, and since it is not a normal USB device, the connection is not established, and micro displays an error message. Tester for USB communication ports Circuit Diagram List of Components 1 Red LED 1 Led Yellow 1 Green LED 3 per 1k 1/8W Resistors 1 USB connector male Simple Test for USB communication ports Indications of LEDs when lit: Red - Polarization USB port was mounted inverted Yellow - Wire USB port data were linked inverted All Deleted - No power to the USB port Green and yellow lights flashing 3 times when turned on - Normal Operation