I have Quectel EC25 module comes with GPRS and GNSS in built, this module needs supply of 3.3V and it's UART works at 1.8V (default Baudrate is 115200) - But i have a processor ATMEGA2560V running at 8Mhz on 3.3V supply.
I am trying to interface that module with my processor, I have used voltage divider circuit with 1M Ohms resistors to pull down 3.3V of processor to 1.8V, I can see some random values comes in the Serial Monitor and i am unable to send any AT commands.

How do i solve this.? is this need any more reliable Resistor divider circuit.? and i don't have source to get 1.8V to 3.3V level shifter :(

Please help

Thank you