Problems with memory management, fixed by increasing data.reserve(64);

[alches]

Arduino MKRZERO. With default configuration of data.reserve(64); in TinyGSMClientSim800.h at line 940, unable to register to network. After increasing reserved memory amount, hanging after different AT commands execution. Some stability is reached at data.reserve(256); Suppose main problem is using of String class with it's known heap fragmentation issues. Any ideas/recommendations?

TinyGSM version: 0.6.1 Hardware: SIM800 R14.18

Scenario, steps to reproduce

Trying to register to network using modem.init();

Expected result

modem.isNetworkConnected() should return true;

Actual result

returning false;

AT command log

00:01:51.342 -> AT 00:01:51.623 -> AT 00:01:51.623 -> BUAT 00:01:52.232 -> AT 00:01:52.533 -> AT 00:01:52.816 -> AT 00:01:52.816 -> ⸮AT 00:01:53.424 -> AT 00:01:53.752 -> AT 00:01:54.033 -> AT 00:01:54.363 -> AT 00:01:54.644 -> AT 00:01:54.644 -> ⸮AT

00:01:54.644 -> OK 00:01:54.644 -> AT&FZ 00:01:54.644 -> AT&FZ

00:01:54.644 -> OK 00:01:54.644 -> ATE0 00:01:54.644 -> ATE0

00:01:54.644 -> OK 00:01:54.644 -> AT+CPIN? 00:01:54.644 -> 00:01:54.644 -> ERROR 00:01:55.663 -> AT+CPIN? 00:01:55.663 -> 00:01:55.663 -> RDY 00:01:55.663 -> 00:01:55.663 -> +CFUN: 1 00:01:55.663 -> 00:01:55.663 -> ERROR 00:01:56.682 -> AT+CPIN? 00:01:56.682 -> 00:01:56.682 -> +CPIN: READY 00:01:56.682 -> 00:01:56.682 -> +CPIN: READY 00:01:56.682 -> 00:01:56.682 -> OK 00:01:56.682 -> Modem: ATI 00:01:56.682 -> 00:01:56.682 -> SIM800 R14.18 00:01:56.682 -> 00:01:56.682 -> OK 00:01:56.682 -> SIM800 R14.18 00:02:06.656 -> AT+CREG? 00:02:06.656 -> 00:02:06.656 -> Call Ready 00:02:06.656 -> 00:02:06.656 -> SMS Ready 00:02:06.656 -> 00:02:06.656 -> +CREG: 0,1 00:02:06.656 -> 00:02:06.656 -> OK

[SRGDamia1]

Exactly what code are you running? Are you close to your board's memory limits? I don't quite see how increasing the data.reserve helps you.

Also, the modem.init() function doesn't do anything to register on the network. The SIM800 should do that on its own. But you do have to wait for the registration to happen. Depending on how good or bad your service is, the SIM800 might take several minutes before it registers and isNetworkConnected() returns true. You should run waitForNetwork() first.

[alches]

Seems that Scheduler library by Arduino v4.4.0 used is causing problem with String-s used in TinyGSM. Closing this thread. Thanks and sorry for wasting your time