What does the boot pin actually do? Can it be used to reduce the module's power consumption when the module is not required? All recommendations are to pull it low to boot. Can it go hi again to turn off the module? Perhaps there are serial commands I should use to shut the module down when not required.
It looks like to "BOOT" pin of the very common PCB for the module goes to the "ON/OFF" pin of the module itself. It looks like this pin can be held continuously low at power on and the module will power up and boot. It appears to work like a switch that when you press it it pulls the pin low. The switch, if held for a while, toggles the power state of the module. There is also a power down command. I guess that I could use the power down command. (Its not clear if ON/OFF needs to be floating high to do this). I guess to wake it again I can let the BOOT pin float high for a while and then pull it low again, as though the switch was released and then pressed and held. I will try and remember to report back here if I get it working.