How do I increase my NodeMCU GPIO pins?

How do I increase my NodeMCU GPIO pins?

In short, you can connect the GPIO expander to two pins on the NodeMCU. In turn, the GPIO expander will provide you with 8 additional GPIO. So, the net gain is six more pins. Although, if you are using some of the pins for input, you will also need another NodeMCU pin to read interrupts from the GPIO expander.

How do I program PCF8574?

After connecting the I2C Module to LCD, connect the GND and VCC pins of the PCF8574 Module to GND and 5V pins of Arduino. Finally, the SDA and SCL Pins. Connect them to pins A4 and A5 pins of Arduino UNO respectively.

How many GPIO ESP 01 are there?

A common reason people ditch the ESP-01 and go to something more robust (like the ESP-12) is the number of pins available for data inputs/outputs. The ESP-12 has 11 digital GPIOs, and one analog. The ESP-01 has 2 digital GPIOs.

What is PCF8574?

The PCF8574 is a silicon CMOS circuit. It provides general purpose remote I/O expansion for most microcontroller families via the two-line bidirectional bus (I2C). It also possesses an interrupt line (INT) which can be connected to the interrupt logic of the microcontroller.

Why is ESP-01 not booting with load on IO pin 2?

I’m using an ESP-01 to control a load (SSR), which is connected to IO pin 2. This pin needs to be HIGH at boot time, otherwise the module won’t boot. I’ve tried driving the load with an optocoupler to avoid driving the pin LOW while booting, but it’s not working.

Are there any I / O pins in esp8266-01?

The ESP8266-01 is the smallest ESP8266 module and only has 8 pins. Of these VCC, GND, RST (reset) and CH_PD (chip select) are not I/O pins but are needed the operation of the module. This leaves GPIO0, GPIO2, TX and RX available as possible I/O pins, but even these have pre-assigned functions.

Why is my ESP8266 not booting properly?

The ESP8266 can be prevented from booting if some pins are pulled LOW or HIGH. The following list shows the state of the following pins on BOOT: There are certain pins that output a 3.3V signal when the ESP8266 boots.

How many GPIOs are in an esp01 expander?

Three hardware address pins allow the use of up to eight devices Polarity reversing register for setting the polarity of the input port data Step 3: ESP01 Can Have 128 GPIOs! An example that shows the magnitude of this expander is its use with ESP01, which can be connected to up to eight expanders with only two IOS, reaching 128 GPIOs.