6x6 keypad

Hi guys
Hope you're all fine in this chaos

I have a question
I'm trying to connect 6x6 keypad to esp32
But unfortunately there isn't enough i/o on that microcontroller (in my condition)
What should i do?
Is there any IC i can use for this purpose?
Maybe a serial or i2c interface??
Thanks in advance

Look for PCF8575 expander board.

"The SX1509 is a 16-channel GPIO expander with an I2C interface – that means with just two wires, your microcontroller can interface with 16 fully configurable digital input/output pins. But the SX1509 can do so much more than just simple digital pin control. It can produce PWM signals, so you can dim LEDs. It can be set to blink or even breathe pins at varying rates. This breakout is similar to a multiplexer or "mux," in that it allows you to get more IO from less pins. And, with a built-in keypad engine, it can interface with up to 64 buttons set up in an 8x8 matrix."

There are breakout boards available and a library from Sparkfun. Great IC!

example of 7 Leds and 16 buttons on i2c:

Paul__B:
Look for PCF8575 expander board.

Thanks i look it up

noiasca:
"The SX1509 is a 16-channel GPIO expander with an I2C interface – that means with just two wires, your microcontroller can interface with 16 fully configurable digital input/output pins. But the SX1509 can do so much more than just simple digital pin control. It can produce PWM signals, so you can dim LEDs. It can be set to blink or even breathe pins at varying rates. This breakout is similar to a multiplexer or "mux," in that it allows you to get more IO from less pins. And, with a built-in keypad engine, it can interface with up to 64 buttons set up in an 8x8 matrix."

There are breakout boards available and a library from Sparkfun. Great IC!

example of 7 Leds and 16 buttons on i2c:

Thanks i bought one

good choice! The Sparkfun library makes reading of the button matrix very easy.