aderregibus
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Hello,
I am using the SIM900 to establish a GPRS connection using PPP protocol over serial port.
That is working perfectly.
But I want to use the DTR pin to switch from data mode to command mode in order to send a few AT commands and then return to data mode again.
I am configuring DTR with AT&D1.
I am also configuring AT+CSCLK=0 to avoid entering sleep mode with DTR.
My problem is that I need to wait for at least 2 or 3 seconds, after pulling DTR low and then high again, before the modem replies to any AT command.
Is this ok? Should it take the modem as long as 3 seconds to start responding to AT commands?
It seems like a great deal of time to leave a data connection waiting...
I appreciate your help.
Regards,
Agustin
I am using the SIM900 to establish a GPRS connection using PPP protocol over serial port.
That is working perfectly.
But I want to use the DTR pin to switch from data mode to command mode in order to send a few AT commands and then return to data mode again.
I am configuring DTR with AT&D1.
I am also configuring AT+CSCLK=0 to avoid entering sleep mode with DTR.
My problem is that I need to wait for at least 2 or 3 seconds, after pulling DTR low and then high again, before the modem replies to any AT command.
Is this ok? Should it take the modem as long as 3 seconds to start responding to AT commands?
It seems like a great deal of time to leave a data connection waiting...
I appreciate your help.
Regards,
Agustin