Signshine FAQ for SMS Modem (An) GPRS industrial 3G modem SMS Networking RS232/RS485 I/O port

Signshine FAQ for SMS Modem

1.Why modem can’t send messages?

--Firstly to check whether AT command is workable, and signal is good enough, and SIM card is fastened well

--Enough charge for SIM card traffic?

--Modem baud rate right or not?Sim card short message center number right or not?

--Serial cable(rs232 cable),ok or not?

2.Modem can send SMS but is unable to receive SMS

--To check whether the storage of Sim card/Module is full or not

3.When message stored in the Sim card,but unavailable to read?

--Setup AT^SSMSS=1 command for the modem

4.When I use modem for dial-up, it shows hardware conflict.

--Please check if  the COM port is occupied by other devices, baud rate is correct? or AT command is ok?Flow control shall be “none”

AT+CGDCONT=1,”IP”,”CMNET” shall be correctly filled when dial-up (CMNET is the APN of China Mobile, please fill your local APN)

5.Modem shows error code “777”, “743” when dial-up,and got approved

--Make sure enough the charge of SIM card traffic?  The signal is good enough?

You may reboot your PC or test it with another PC for dial up.


6.There have data loss when use GSM DTU for sending messages to cell phone

--Use another serial tool for testing.

--Check if the baud rate and parity bit of serial tool is the same as S3320

--Check if sending format is accordance with display format.


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