search

xreef / PCF8574_library

PCF8574 library. i2c digital expander for Arduino, Raspberry Pi Pico and rp2040 boards, esp32, SMT32 and ESP8266. Can read write digital values with only 2 wire. Very simple to use and encoder support.
Other
216 stars 62 forks source link

Can we use multiple digital pins of Arduino? #27

Closed amandugar closed 4 years ago

amandugar commented 4 years ago

Can we use multiple Digital pins of Arduino like if we are using pin 2 to connect 8 pcf8574. Similarly, can we use 8 pcf8574 with pin 3 together with pin 2 if yes please explain me how to do it

xreef commented 4 years ago

Hi amandugar, you can use multiple i2c channel to connect 8 pcf8574 each one by changing the address of pcf8574. For esp32 you can configure TwoWire to do that. More information here https://www.mischianti.org/category/my-libraries/pcf8574/ . Bye Renzo

amandugar commented 4 years ago

It's not that what i asked

xreef commented 4 years ago

Sorry I don't understand, please try to explain better..

amandugar commented 4 years ago

It's like we can use 1 digital pin of Arduino Uno to connect 8 PCF8574. As Arduino UNO has 14 Digital IO pins so can we connect more PCF8574? Or if we want more the 64 pins Can we Master-Slave I2c using Wire.h or else how to do it if we want more then that

xreef commented 4 years ago

Hi Amandugar, now I undestand, the i2c protocol need 2 pin, so you can't use only one pin to manage pcf8574. Bye Renzo