Quectel EC25 User Manual

LTE Module Series
EC25&EC21 AT Commands Manual
EC25&EC21_AT_Commands_Manual 143 / 231
<mr> Please refer to AT+CMGS.
1. For concatenated messages, the maximum length will be reduced by the length of the user data
header (UDH). 3GPP TS 23.040 defines two kinds of UDH length: 6 bytes and 7 bytes, so the two
kinds of <uid> are 8-bit (6 bytes) and 16-bit (7 bytes). AT+QCMGS uses 8-bit <uid>.
 In the case of GSM 7 bit default alphabet data coding scheme, the maximum length of each
segment of a concatenated message is (140 octets - 6 )*8/7=153 characters.
 In the case of 16 bit UCS2 data coding scheme, the maximum length of each segment is
(140-6)/2=67 characters.
 In the case of 8-bit data coding scheme, the maximum length of each segment is 140-6=134
characters.
2. <mr> Message-Reference field gives an integer representation of a reference number of the
SMS-SUBMIT or SMS-COMMAND submitted to the SC by the MS, and it is used to confirm
whether the SMS-DELIVER has been received from SC duplicate or not.
<uid> The field of UDH. It is message identification of the concatenated SMS, which is different
from <mr>. Each segment in a concatenated message should have the same <uid>, but
<mr> must be incremented for each segment of a concatenated message.
3. AT+QCMGS does not support to send message in PDU mode (AT+CMGF=0).
Example
AT+CMGF=1 //Set SMS message format as text mode
OK
AT+CSCS="GSM" //Set character set as GSM which is used by the TE
OK
AT+QCMGS="15056913384",120,1,2 <CR> //Input 120 for <uid>, and send the first segment of the
concatenated SMS
>ABCD<Ctrl-Z>
+QCMGS: 190
OK
AT+QCMGS="15056913384",120,2,2 <CR> //Send the second segment of the concatenated SMS.
>EFGH<Ctrl-Z>
+QCMGS: 191
OK
NOTES

Quectel EC25 Specifications

General

Category	LTE Module
LTE TDD	B38/B40/B41
WCDMA	B1/B5/B8
GSM	850/900/1800/1900 MHz
Data rates	LTE Cat 4: 150 Mbps DL/50 Mbps UL
GNSS	GPS/GLONASS/BeiDou/Galileo/QZSS
Operating Temperature	-40°C to +85°C
Form Factor	LCC
Storage Temperature	-45°C to +90°C
SIM Interface	1.8V/3.0V
Antenna Interface	Main, Diversity, GNSS
LTE FDD	B1/B3/B5/B7/B8/B20
Interfaces	USB 2.0, UART, PCM, GPIO
Operating Voltage	3.3V - 4.3V
Protocols	TCP/IP, UDP, FTP, HTTP, HTTPS
Certifications	CE, FCC, PTCRB, GCF, RCM, IC