SIM7000A modem.sendSMS return is not reliable

rrrrpa
Newbie

Posts: 32

SIM7000A modem.sendSMS return is not reliable Feb 10, 2024 18:21:50 GMT

Quote

Post by rrrrpa on Feb 10, 2024 18:21:50 GMT

I have been fighting a problem where the return from modem.sendSMS is not reliable. I find the sendSMS is always successful but the return routinely reports that it failed. After much frustration I dove into the library to better understand what's happening.

I have identified an issue in the library for "boolean Botletics_modem::sendSMS(const char *smsaddr, const char *smsmsg)".

According to the library for the SIM7000A, two CRLFs are expected prior to the +CMGS reply.

THIS IS WRONG. I have replaced the code with:

for (int i = 0; i < 3; i++) {

readline(30000); // look for the +CMGS reply, wait up to 30s

DEBUG_PRINT("sendSMS: i = "); DEBUG_PRINT(i);

DEBUG_PRINT("\tlength = "); DEBUG_PRINT(strlen(replybuffer));

DEBUG_PRINT("\tcontent = "); DEBUG_PRINTLN(replybuffer);

if (strstr(replybuffer, "+CMGS") != 0) {

readline(1000); // read the OK reply

DEBUG_PRINT("sendSMS: i = "); DEBUG_PRINT(i);

DEBUG_PRINT("\tlength = "); DEBUG_PRINT(strlen(replybuffer));

DEBUG_PRINT("\tcontent = "); DEBUG_PRINTLN(replybuffer);

if (strstr(replybuffer, "OK") != 0) {

return true;

}

return false;

}

}

return false;

and found that sometimes 2 each CRLFs are returned, but usually neither is returned and the +CMGS reply is immediately received. MAYBE THIS IS A TIMING ISSUE? Has anyone else experienced the same? Am I overlooking something?

Please see the captured evidence below (phone number is modified). All of the captured show no CRLFs, and the 2:00 and 5:00 SMSs reportedly failed due to what looks to me to be a GMT time stamp? Neither failed; both were received.

01:00:16.255 -> Requesting Network Status

01:00:16.288 -> ---> AT+CGREG?

01:00:16.288 -> <--- +CGREG: 0,1

01:00:16.320 -> Network status = 1 -> Registered (home)

01:00:16.353 -> Sending SMS:

01:00:16.389 -> ---> AT+CMGF=1

01:00:16.389 -> <--- OK

01:00:16.423 -> ---> AT+CMGS="001925......."

01:00:16.966 -> <--- >

01:00:17.636 -> sendSMS: i = 0 length = 10 content = +CMGS: 137

01:00:17.702 -> sendSMS: i = 0 length = 2 content = OK

01:00:17.734 -> sendSMS was Successful

02:00:45.000 -> Requesting Network Status

02:00:45.033 -> ---> AT+CGREG?

02:00:45.033 -> <--- +CGREG: 0,1

02:00:45.066 -> Network status = 1 -> Registered (home)

02:00:45.098 -> Sending SMS:

02:00:45.132 -> ---> AT+CMGF=1

02:00:45.132 -> <--- OK

02:00:45.178 -> ---> AT+CMGS="001925......."

02:00:45.678 -> <--- >

02:00:47.331 -> sendSMS: i = 0 length = 6 content = DST: 0

02:00:47.396 -> sendSMS: i = 1 length = 35 content = *PSUTTZ: 24/02/05,10:00:46","-32",0

02:01:17.742 -> sendSMS: i = 2 length = 0 content =

02:01:17.783 -> sendSMS Failed

03:00:30.305 -> Requesting Network Status

03:00:30.337 -> ---> AT+CGREG?

03:00:30.337 -> <--- +CGREG: 0,1

03:00:30.370 -> Network status = 1 -> Registered (home)

03:00:30.403 -> Sending SMS:

03:00:30.435 -> ---> AT+CMGF=1

03:00:30.435 -> <--- OK

03:00:30.468 -> ---> AT+CMGS="001925......."

03:00:31.008 -> <--- >

03:00:31.845 -> sendSMS: i = 0 length = 10 content = +CMGS: 139

03:00:31.877 -> sendSMS: i = 0 length = 2 content = OK

03:00:31.910 -> sendSMS was Successful

04:00:13.041 -> Requesting Network Status

04:00:13.074 -> ---> AT+CGREG?

04:00:13.107 -> <--- +CGREG: 0,1

04:00:13.107 -> Network status = 1 -> Registered (home)

04:00:13.172 -> Sending SMS:

04:00:13.172 -> ---> AT+CMGF=1

04:00:13.206 -> <--- OK

04:00:13.206 -> ---> AT+CMGS="001925......."

04:00:13.765 -> <--- >

04:00:14.307 -> sendSMS: i = 0 length = 10 content = +CMGS: 140

04:00:14.339 -> sendSMS: i = 0 length = 2 content = OK

04:00:14.373 -> sendSMS was Successful

05:00:30.310 -> Requesting Network Status

05:00:30.342 -> ---> AT+CGREG?

05:00:30.342 -> <--- +CGREG: 0,1

05:00:30.375 -> Network status = 1 -> Registered (home)

05:00:30.407 -> Sending SMS:

05:00:30.440 -> ---> AT+CMGF=1

05:00:30.440 -> <--- OK

05:00:30.473 -> ---> AT+CMGS="001925......."

05:00:31.026 -> <--- >

05:00:32.594 -> sendSMS: i = 0 length = 6 content = DST: 0

05:00:32.627 -> sendSMS: i = 1 length = 35 content = *PSUTTZ: 24/02/05,13:00:31","-32",0

05:01:02.986 -> sendSMS: i = 2 length = 0 content =

05:01:03.028 -> sendSMS Failed

06:00:15.320 -> Requesting Network Status

06:00:15.352 -> ---> AT+CGREG?

06:00:15.385 -> <--- +CGREG: 0,1

06:00:15.385 -> Network status = 1 -> Registered (home)

06:00:15.451 -> Sending SMS:

06:00:15.451 -> ---> AT+CMGF=1

06:00:15.451 -> <--- OK

06:00:15.483 -> ---> AT+CMGS="001925......."

06:00:16.007 -> <--- >

06:00:16.786 -> sendSMS: i = 0 length = 10 content = +CMGS: 142

06:00:16.818 -> sendSMS: i = 0 length = 2 content = OK

06:00:16.851 -> sendSMS was Successful

07:00:26.333 -> Requesting Network Status

07:00:26.366 -> ---> AT+CGREG?

07:00:26.400 -> <--- +CGREG: 0,1

07:00:26.400 -> Network status = 1 -> Registered (home)

07:00:26.432 -> Sending SMS:

07:00:26.465 -> ---> AT+CMGF=1

07:00:26.497 -> <--- OK

07:00:26.497 -> ---> AT+CMGS="001925......."

07:00:27.022 -> <--- >

07:00:27.849 -> sendSMS: i = 0 length = 10 content = +CMGS: 143

07:00:27.882 -> sendSMS: i = 0 length = 2 content = OK

07:00:27.915 -> sendSMS was Successful

08:00:39.063 -> Requesting Network Status

08:00:39.096 -> ---> AT+CGREG?

08:00:39.129 -> <--- +CGREG: 0,1

08:00:39.129 -> Network status = 1 -> Registered (home)

08:00:39.194 -> Sending SMS:

08:00:39.194 -> ---> AT+CMGF=1

08:00:39.227 -> <--- OK

08:00:39.227 -> ---> AT+CMGS="001925......."

08:00:39.790 -> <--- >

08:00:40.398 -> sendSMS: i = 0 length = 10 content = +CMGS: 144

08:00:40.431 -> sendSMS: i = 0 length = 2 content = OK

08:00:40.507 -> sendSMS was Successful

Botletics
Administrator

Posts: 117

SIM7000A modem.sendSMS return is not reliable Feb 18, 2024 2:00:59 GMT

Quote

Post by Botletics on Feb 18, 2024 2:00:59 GMT

Yea it looks like the network time stamp field is getting in the way of the response. I'm guessing your code's timing is such that right about the time when it starts to send the SMS, it's also just about connected to the network and gets a network time stamp. Let me see if there's a way to prevent the network time stamp from showing up...

Botletics Administrator Posts: 117	SIM7000A modem.sendSMS return is not reliable Feb 18, 2024 2:12:17 GMT Quote Select Post Deselect Post Link to Post Member Give Gift Back to Top Post by Botletics on Feb 18, 2024 2:12:17 GMT Try and see if running `modem.enableRTC(false);` in setup() would help with the PSUTTZ network time stamp?

rrrrpa Newbie Posts: 32	SIM7000A modem.sendSMS return is not reliable Feb 18, 2024 23:00:37 GMT Quote Select Post Deselect Post Link to Post Member Give Gift Back to Top Post by rrrrpa on Feb 18, 2024 23:00:37 GMT I added it. Let's give it some run time to see what happens.

rrrrpa
Newbie

Posts: 32

SIM7000A modem.sendSMS return is not reliable Feb 19, 2024 3:39:12 GMT

Quote

Post by rrrrpa on Feb 19, 2024 3:39:12 GMT

modem.enableRTC(false); was added in setup() as suggested. A failure case is follows. 3 consecutive readline(5000) failed

Here's my modified boolean Botletics_modem::sendSMS(const char *smsaddr, const char *smsmsg) :

for (int i = 0; i < 3; i++) {
readline(5000); // look for the +CMGS reply, wait up to 30s
DEBUG_PRINT("sendSMS reply: i = "); DEBUG_PRINT(i);
DEBUG_PRINT("\tlength = "); DEBUG_PRINT(strlen(replybuffer));
DEBUG_PRINT("\tcontent = "); DEBUG_PRINTLN(replybuffer);

if (strstr(replybuffer, "+CMGS") != 0) {
readline(1000); // read the OK reply
DEBUG_PRINT("sendSMS reply: i = "); DEBUG_PRINT(i);
DEBUG_PRINT("\tlength = "); DEBUG_PRINT(strlen(replybuffer));
DEBUG_PRINT("\tcontent = "); DEBUG_PRINTLN(replybuffer);

if (strstr(replybuffer, "OK") != 0) {
return true;
}
return false;
}
}
return false;
}

16:00:02.803 -> Started Weather Report *********************************************************************
16:00:02.901 ->
16:00:02.935 -> Requesting Network Info
16:00:02.935 -> ---> AT+CPSI?
16:00:03.036 -> <--- +CPSI: LTE CAT-M1,Online,310-260,0x411F,21294086,47,EUTRAN-BAND12,5035,2,2,-8,-89,-67,18
16:00:03.135 -> ---> AT+COPS?
16:00:03.135 -> <--- +COPS: 0,0,"T-Mobile",7
16:00:03.167 ->
16:00:03.167 -> Requesting Network Status
16:00:03.200 -> ---> AT+CGREG?
16:00:03.233 -> <--- +CGREG: 0,1
16:00:03.233 -> Network status = 1 -> Registered (home)
16:00:03.299 ->
16:00:03.299 -> Requesting Network Strength / RSSI
16:00:03.331 -> ---> AT+CSQ
16:00:03.331 -> <--- +CSQ: 25,99
16:00:03.364 -> RSSI = 25 -> -64 dBm
16:00:03.397 -> weatherStation txtMsg[0] = $
16:00:03.429 ->
16:00:03.429 -> Preparing Weater Report *********************************************************************
16:00:03.528 -> Sending default SMS weather report to 0019252345805. Length = 134
16:00:03.593 -> 4R WEATHER @ 16:00
16:00:03.593 -> Temp: 71
16:00:03.626 -> Hi: 71 @ 15:49
16:00:03.626 -> Lo: 70 @ 15:24
16:00:03.659 -> Hum: 53%
16:00:03.659 -> BP: 29.26"
16:00:03.659 -> Wind: 225 @ 0 / 4 mph
16:00:03.692 -> Rain: 0.418 / 0.418"
16:00:03.725 -> RSSI: -64 dBm
16:00:03.725 ->
16:00:03.725 -> Requesting Network Status
16:00:03.757 -> ---> AT+CGREG?
16:00:03.757 -> <--- +CGREG: 0,1
16:00:03.789 -> Network status = 1 -> Registered (home)
16:00:03.823 -> Sending SMS:
16:00:03.856 -> ---> AT+CMGF=1
16:00:03.856 -> <--- OK
16:00:03.888 -> ---> AT+CMGS="0019252345805"
16:00:04.440 -> <--- >
16:00:09.603 -> sendSMS reply: i = 0 length = 0 content =
16:00:14.673 -> sendSMS reply: i = 1 length = 0 content =
16:00:19.740 -> sendSMS reply: i = 2 length = 0 content =
16:00:19.772 -> sendSMS Failed
16:00:19.772 -> Completed Weather Report ********************************************************************

Botletics Administrator Posts: 117	SIM7000A modem.sendSMS return is not reliable Feb 21, 2024 12:32:56 GMT via mobile Quote Select Post Deselect Post Link to Post Member Give Gift Back to Top Post by Botletics on Feb 21, 2024 12:32:56 GMT You decreased the wait time from 30s to 5s.

rrrrpa Newbie Posts: 32	SIM7000A modem.sendSMS return is not reliable Feb 21, 2024 15:24:10 GMT Quote Select Post Deselect Post Link to Post Member Give Gift Back to Top Post by rrrrpa on Feb 21, 2024 15:24:10 GMT It did not make any difference. I will put it back to 30s and continue testing.

rrrrpa
Newbie

Posts: 32

SIM7000A modem.sendSMS return is not reliable Feb 22, 2024 1:19:38 GMT

Quote

Post by rrrrpa on Feb 22, 2024 1:19:38 GMT

I have found that elapsed time to get the 2 "readline" responses from Botletics_modem::sendSMS is anywhere from 250 msec to 74 SECONDS!

Botletics_modem::sendSMS has:

// Eat two sets of CRLF"
readline(200);
readline(200);

This is in error. Only 2 responses are received, not 4. Here's my code:

unsigned long myTime = millis();
for (int i = 0; i < 3; i++) {
readline(30000); // look for the +CMGS reply, wait up to 30s
Serial.print(F("sendSMS reply: i = ")); Serial.print(i);
Serial.print(F("\tlength = ")); Serial.print(strlen(replybuffer));
Serial.print(F("\tcontent = ")); Serial.println(replybuffer);

if (strstr(replybuffer, "+CMGS") != 0) {
readline(1000); // read the OK reply
Serial.print(F("sendSMS reply: i = ")); Serial.print(i);
Serial.print(F("\tlength = ")); Serial.print(strlen(replybuffer));
Serial.print(F("\tcontent = ")); Serial.println(replybuffer);

if (strstr(replybuffer, "OK") != 0) {
myTime = millis() - myTime;
Serial.print(F("Elapsed time (msec) = ")); Serial.println(myTime);
return true;
}
Serial.print(F("sendSMS Elapsed Time (msec) = ")); Serial.println(myTime);
return false;
}
}

myTime = millis() - myTime;
Serial.print(F("Elapsed time (msec) = ")); Serial.println(myTime);

return false;

And a typical response:

17:15:18.670 -> Network status = 1 -> Registered (home)

17:15:18.748 -> Sending SMS:

17:15:21.578 -> sendSMS reply: i = 0 length = 10 content = +CMGS: 142

17:15:21.610 -> sendSMS reply: i = 0 length = 2 content = OK

17:15:21.676 -> Elapsed time (msec) = 2158

17:15:21.709 -> sendSMS was Successful

BTW - I'm on T-Mobile if that makes a difference.

SIM7000A modem.sendSMS return is not reliable

Post by rrrrpa on Feb 10, 2024 18:21:50 GMT

Post by Botletics on Feb 18, 2024 2:00:59 GMT

Post by Botletics on Feb 18, 2024 2:12:17 GMT

Post by rrrrpa on Feb 18, 2024 23:00:37 GMT

Post by rrrrpa on Feb 19, 2024 3:39:12 GMT

Post by Botletics on Feb 21, 2024 12:32:56 GMT

Post by rrrrpa on Feb 21, 2024 15:24:10 GMT

Post by rrrrpa on Feb 22, 2024 1:19:38 GMT