DOTA in Q2501

DOTA is working fine when the module(Q2501) is connected via serial port. But, when the serial link is removed, DOTA continues and stops at adl_adInstall and it stays there until i connect the serial cable. Immediately after connecting the cable, the DOTA completes successfully and installs the versions that was uploaded. What is the reason for this behavior? How to overcome this?
This issue is not seen in Q2686.

S. Vanee

Does this help: viewtopic.php?f=4&t=428&p=10232&hilit=CREDIT#p10232

Thanks Awneil for your help. The options provided in the link:
Option 1. Design your hardware to pull the CTS line so the Wavecom processor things there is a serial cable connected.

Option 2: When the code is ready to apply the DOTA file, issue a “at+wrst” to be executed two minutes later. Issue the adl_install() command. The idea is that ff the adl_install does not reset the Wavecom modem, the the at+wrst will do so anyway two minutes later

Option 3: When the DOTA file is finished downloading, just set a non-volatile flag and reboot the WMP with a normal at+cfun=1 command. When it starts up it first checks the flag. If set, it disables all debug info and unsollicted responses to UART1. It then clears the flag and executes the adl_install() which works now because there is nothing on serial port.

Out of these Option 2 didnt workout for me. Does wrst actually work? Because the unit never resetted. Im going to try Option 3. Hope this would work out.

S. Vanee