+CMS ERROR: 304, sending message using at command

sms gsm at-command modem pdu
javinc picture javinc · May 20, 2015 · Viewed 18.6k times · Source

Im new to GSM and AT command sets,

based on the error +CMS ERROR: 304 its a Invalid PDU mode parameter according to activexperts

Im trying to send message using AT command to GSM modem in PDU mode

AT+CMGF=0
OK

AT+CMGS=31
> 079136190700203911000C913639350768260000AA13C834A89D07B9C3ED32283D0751C3F3F41B

+CMS ERROR: 304

Can you help me guys what did I missed or mistake? I used this to encode the PDU

Thanks guys.

Answer

user2543882 picture user2543882 · May 20, 2015

Try by chaning PDU mode. Use the following command:

AT + CMGF = 1

If you are trying to Send SMS try AT + CMGF = 1 first and then again AT+CMGS="NUMBER" and hope after typing the message on > prompt, you are using CTRL+Z key combination to send SMS.

Related questions

Why I am not able to receive sms using AT commands?

I want to send / receive sms using AT commands from my computer to my mobile phone. I connected my phone to my computer using a USB port. My computer detects the modem and I am able to send sms from …

Read More
AT+CMGS returns ERROR

I am using SIM900 GSM module connect to my AVR Microcontroller. I tested it with FT232 to see transmitting data. First Micro sends AT it will response OK AT OK AT+CMGF=1 OK AT+CMGS="+9893XXXXXX" returns ERROR and doesn't …

Read More
Sending Unicode Messages (such as in Persian and Arabic) in C# using AT Commands through GSM Modem

I am developing an application for GSM Modems (D-Link DWM-156) in C#.Net using AT commands. I have a problem sending Unicode messages (Such as messages written in Persian or Arabic). Here it is the core of my program: SerialPort …

Read More