The modem hardware_reset is not working

[hosseinkalbasi]

Bug Description

The modem hardware reset is not working with the GPIO approach, causing the following error in this library

('Module boot message not found in requisite time - aborting', '')

I managed to replace the reset_hardware method with another method to reset the modem via an AT command that is turning the flight mode on and off (as far as I understood):

AT+CFUN=0 then AT+CFUN=1

This will return the messages that the library expects

required_msgs = [
            '+CPIN: READY', 'Call Ready', 'SMS Ready'
        ]

However, the hardware reset via GPIO would still be preferred. I tried with PINs 4 and 7 and neither worked. I am using the GPRS hat here with Raspberry Pi 3B

To Re-produce

Initialize the library on Rpi 3 - serial_port /dev/ttyS0