In process now to try to optimize the HL7 low power modes but having difficulty ever getting there.
The Microprocessor to the HL700 is connected with a 3 wire UART connection.
But it seems that some power setting modes are dependant on the DTR pin.
Though we try to configure +KSLEEP mode to be in standalone mode and using some sample edrx commands found in the HL7800 Low Power Modes Application Note, we can never achieve anything close to low power. We find that our board always consumes around 130mA, turning off the radios with CFUN we can get it down to 60mA.
Is it recommended to not use a 3 wire UART?
If the HL7800 never gets associated with a cell tower, will it prevent it from going into low power mode? I’m asking because currently, our prototype is in a room where no cell connection can be made.
Any guidance is appreciated.