I have some problems with HL6528-2.8V after reset.
After power is up, we inialize modem and work with it (send SMS, call and ect.).
Through some time I make reset sequence and after I make power up sequence. Signal on RESET_IN and PWR_ON pins are OK (I’he checked it).
Buts after power up sequence modem stalls (no answer for AT command).
modem software version is 0.12
Could anybody help me.
The firmware you have is REALLY old, it must be one of the first units to have been released to customers, I am not surprised you are having problems with it.
You really need to try to have it updated, your distributor app engineer has access to the files and tools to do this but essentially you need to ensure you have access to the UART either directly or using the micro processor as a proxy (for which there are a few timing/processing rules). You will then be able to download the firmware to the unit from a windows PC.