Help, wrong character set when receiveing SMS from RV50


I am using RV50 on a out-door screen project. The MCU controls RV50 by serial port. RV50 was updated to newest version of firmware.

I send SMS to report status

AT*SMSM2M=“1234555523 voltage=12.487V output=[good] display on”

What I got from my phone is

voltage=12.487V output=ÄgoodN display on

The ‘[’ was replcaed by ‘Ä’ and ‘]’ was replaced by “~ above N” (I can’t input the char)

How could I set the RV50 to send pure ascii SMS?

If I want a “New Line” in SMS, what should I do? I tried to incert ‘\x0A’ in SMS but got “ERROR”.

One more thing, according to the “4111108_ALEOS 4.9.0 software configuration” - Page441,
“AT*SMSM2M_8 sends an 8-bit SMS (requires quotation marks;maximum 140 characters)”

I have tested it and the maximun characters are 114, NOT 140. Plus all the chars, the at command, phone number, quotation marks and CR , there are exactly 256 bytes. Is there some bug in this command?


After some reseach, find the characters set is GMS standard. The ‘[’ , ‘]’ and some symbols are “Extended Characters” in GSM standard which should be prefixed with the escape character (1B).

If I use AT*SMSM2M=“1234555523 [” to send a sms, I got the ‘Ä’. ‘[’ (ascii=0x3C) was translated to 0xC4

If I use AT*SMSM2M=“1234555523 \x1B\x3C”, I acturely got 0x3C which is ‘<’. The escape character was ignored by RV50.

If I use AT*SMSM2M_8=“1234555523 1B3C”, it works. I got ‘[’

But as I said before, using AT*SMSM2M_8 can only send 114 bytes.

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