ESP8266 Community Forum

- Tue Feb 23, 2016 12:48 am #41694 I am using a ESP-02 module.
I have connected a sensor to the GPIO0 pin of the module to send sensor data to the cloud every 10 seconds.
I have used arduino IDE to successfully program the module with GPIO0 connected to GND,VCC and CH_PD to +3.3V Supply,UTXD to RXD of TTL and Vice versa.

But when i reset the power to the module,with the GPIO0 pin connected to the sensor,it goes to boot mode.When i disconnect the GPIO0 from the sensor and then resetting the module will work normally.
Please help me with this...
How to make it work normally to work at startup???

- Tue Feb 23, 2016 4:31 pm #41754 What kind of sensors ?
If it only logic level, you can use inverter logic to make it HIGH when sensors is in idle.
Simply use a NPN transistor or N-Channel MOSFET and invert the logic in your code.
Otherwise, you will need an ESP with more pins such ESP-12.

- Tue Feb 23, 2016 10:57 pm #41774 its an hall effect sensor which gives a pulse output.

Can i connect it to GPIO2 pin????

- Wed Feb 24, 2016 8:58 am #41798 GPIO2 has the same limitation as GPIO0 : it need to be HIGH at power-up and/or reset to get into proper boot mode.