Does the EC21 module support Long Message Service (LMS)?

IoT Modules LTE Standard Module
1

Hello there,

I’m wondering, does the EC21 module support Long Message Service (LMS/2,000byte)?"

2

Text-mode or PDU-mode?

The size should make no difference in PDU-mode.

3

Is it possible to send long messages, such as LMS of up to 2,000 bytes, regardless of whether in TEXT mode or PDU mode?

4

All SMSs travel over-the-air as PDUs.

With a modem in text-mode, the modem is responsible for all conversions between text and PDUs.

So support for long messages in text-mode depends entirely on the capabilities of modem firmware.

In PDU-mode, the modem is given the long message parts pre-encoded. Likewise, decoding of multi-part SMSs in PDU-mode is the responsibility of software external to the modem.

256 message parts each containing 153 7-bit characters from the GSM default alphabet are theoretically possible in PDU mode.

If a message uses even a single character which is not in the GSM default alphabet, then the entire message (including all parts) must use 16-bit UCS-2 encoding. This reduces the payload size by more than 50%

Not all modems support UCS-2 in text-mode.

I don’t know the text-mode limitations of the EC21, sorry.