Through AT commands the module can be destried

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What steps will reproduce the problem?
1. I called the following command "AT+CSCLK=1" with the library: 
gsm.SimpleWriteln("AT+CSCLK=1");

Now the GSM module will not start any longer. If I make the power on process 
manually like described in the datasheet, the SIM900 will partly communicate, 
but produces a lot of errors. I listened on the UART and it looks like this:
AT
AT
AT
AT
AT
AT
AT
AT
AT
AT&F
ATE0
AT+CLIP=1
AT+CMEE=0
AT+CMEE=0
AT+CMEE=0
AT+CMEE=0
AT+CMEE=0
AT+CMGF=1
AT+CMGF=1
AT+CMGF=1
AT+CMGF=1
AT+CMGF=1
AT+CNMI=2,0
AT+CNMI=2,0
AT+CPMS="SM","SM","SM"
AT+CPMS="SM","SM","SM"
AT+CPMS="SM","SM","SM"
AT+CPMS="SM","SM","SM"
AT+CPMS="SM","SM","SM"
AT+CPMS="SM","SM","SM"
AT+CPMS="SM","SM","SM"
AT+CPMS="SM","SM","SM"
AT+CPMS="SM","SM","SM"
AT+CPMS="SM","SM","SM"
AT+CPBS="SM"
AT+CPBS="SM"
AT+CPBS="SM"
AT+CPBS="SM"
AT+CPBS="SM"
AT+CIPSHUT
AT+CIPSHUT
AT+CIPSHUT
AT+CIPSHUT
AT+CIPSHUT
ATE0


The autostart of the library only produces this:
AT
AT
...
AT
xxx x x xx x   x f (crazy letters) AT+IPR=9600¦ (more crazy letters)


I tried to reset the module with the following commands:
gsm.SimpleWriteln("ATZ")
gsm.SimpleWriteln("AT&F")

But it was no solution. Then I tried to send the commands through this 
application:
http://m2msupport.net/m2msupport/module-tester/
It is possible to send the commands, and I receive a "OK", but when I try to 
start the module later, I only receive ERROR.


To reset the module through the hardware reset input was also no solution.

Does anybody has an idea?

Original issue reported on code.google.com by [email protected] on 27 Jul 2013 at 8:19