Hi all !
Picture is taken form datasheet.
Lines with X red are not used.
There is NO RESISTOR 5k6 on RXD from uC side (in red), why?
I suppose that form GPRS modules TXD line comes 4,1V and it should be divided by resistors.
Why is resistor divider placed on first line (uC TXD - module RXD) ?
Thank you for explanation !