PCF8574

This 8-bit input/output (I/O) expander for the two-line bidirectional bus (I2C) is designed for 2.5-V to 6-V VCC operation. The PCF8574 device provides general-purpose remote I/O expansion for most microcontroller families by way of the I2C interface (serial clock (SCL), serial data (SDA)). The device features an 8-bit quasi-bidirectional I/O port (P0–P7), including latched outputs with high-current drive capability for directly driving LEDs. Each quasi-bidirectional I/O can be used as an input or output without the use of a data-direction control signal. At power on, the I/Os are high. In this mode, only a current source to VCC is active.

Main Content

ATtiny85 Mario Challenge!

“The ATtiny85 microcontroller is a capable but compact AVR. However with only 8K of program memory, 512 bytes of EEPROM, 512 of SRAM and only 8 pins (3 of which are dedicated to the usual suspects of Vcc, GND and …

Automated Plant Pot - Little Garden

“Looking around for idea’s, I decided to make something usefull for my mother who loves growing plants and began working on an automated plant pot. The main tasks for this automated plant pot, Little Garden, are to: Measure the …

Contactless Water Fountain

“I was looking for a project that would check all the requirements set by my teachers and at the same time be fun for me to make. When looking for a subject I couldn’t help but feel inspired by …

Electromagnetic Lock With Air Monitoring

“I’ve had this issue for a while where people seemingly don’t value my privacy as much as i do myself and just barge into my room whenever they feel like it without any warning. So since i had …

Versatile I/O Extender PCB to Control Many Nixie Tubes With I2C

“Currently there is a lot of interest in bringing vintage nixie tubes to life. Lot’s of nixie tube clock kits are available on the market. There appeared to be even a lively trade on old stock of russian nixie …

Modern and New and Easier Example of Locker With Arduino Matrix Keypad 4x4

“Another example of using a LCD keypad matrix 4x4 with an I2C circuit. This matrix keypad is made of 16 push buttons and with I2c communication, you just need 2 pins to manage it: SDA (A4 on arduino board) and …

Brick a Bottle or Three

“A little game to show how a PCF8574 can be used with a Nokia 5110 screen.”

Esp little game engine

“Game engine using a virtual machine with a simulator and a web compiler Game engine with web emulator and compiler. The image is displayed on the tft using the TFT_eSPI library The game engine has a virtual screen resolution of …

DIY ESP8266-Based Badge

“This badge is a DIY dev board for MicroPython. Based on ESP8266, it has a lot of features which are possible to learn and have fun with! Story This badge was developed due to my need for a board to …

PCF8574 GPIO Extender - With Arduino and NodeMCU

“In my last tutorial, I talked about the TCA9548A MUX which can be used to add at the max of 64 I2C or IC sensors to your Arduino/ESP8266/ESP32. In this tutorial, I am going to talk about the …