Cannot send long (concantenated SMS) with EG25-G

Hi! We have an issue where the Mulritech L4G1 modem will stop responding and encounter error when we send long SMS (concantenated).

The modem information: Quectel EG25 Revision: EG25GGBR07A08M2G, MODEM-IMEI: 860195052143028

Happen on all L4G1 modems.

Can you advise?

The modem simply does not respond to any AT command after sending a few messages. We are using Linux kernel 4.19.134

Please assist

Hello Jswong,
You can use AT+QCMGS send Concatenated Messages, the specific reference method is shown in the picture below, thank you.

Hi! We are using PDU mode. Any pointers when we send in PDU mode? We face Error 350 when sending long message with long message.

This is a huge topic, with so many individual aspects of PDU encoding to get correct.

Can you provide an example set of your PDUs for a single (failing) concatenated message? By all means use a token destination address rather than a real one.

hi Jswong,
For PDU mode, you need execute AT+CMGF=0 to query the message formate is PDU mode, then you can send PDU message.