MDM2 built-in module is the second interface between Python and the module internal AT command handling. It is used to send AT commands from Python script to module and receive AT responses from module to Python script when the classic MDM built-in module is already in use.
Though MDM2 built-in module is independent from activation of CMUX protocol, it works on the second instance of AT parser in the same way the second CMUX port does. So the rules on AT commands that apply on the first and second CMUX ports (AT parser instances) apply on MDM and MDM2 as well.
See "AT Commands Reference Guide" and "CMUX User Guide" for details on availability of AT commands on all instances and for the rules on parallel execution of AT commands on two instances.
In the default configuration, echo (ATE0) is disabled and the response format of result codes is set to verbose (ATV1).
If you want to use MDM2 built-in module you need to import it:
import MDM2
than you can use its methods like in the following example:
a = MDM2.send('AT', 0)
b = MDM2.sendbyte(0x0d, 0)
c = MDM2.read()
which sends 'AT' and reads 'OK' response.
More details about MDM2 built-in module methods can be found in the following paragraphs.