Electron Cyan-Blinking, SOS, dark,

I just updated a bunch of electrons to latest version (0.8.0rc11). After I had issues with 2 devices I changed keys of those (particle keys doctor ) without success. For some reason, one of the devices recovered by “magic”.

The other one doesn’t work til now. And I had similar issues already months ago,…

The code is:

STARTUP(cellular_credentials_set("em", "", "", NULL));
SerialLogHandler logHandler(LOG_LEVEL_ALL); // DEBUG

void setup() {

void loop(void) {

The result is:

  • Device doesn’t connect to cloud
  • Device breathes white, then flashing green, flashing cyan, dark(!?)
  • or (also very cool!!): white, flashing green, steady cyan
    or any other combination with a little red, some SOS, some …

What did I do to recover?

  • Downgrade back to 0.8.0rc1
  • change protocol to TCP and back to UDP (with keys-doctor afterwards)
  • change SIM card to another from the same provider as well as to another provider

I had similar issues with other electrons in the past. The only thing that really helped was a hardware-watchdog and very handsome customers. But I rather would like to have a working device,…

I have also tons of loggings of the modem-communication, eg:

mbedtls/library/ssl_tls.c:2330: handshake timeout
mbedtls/library/ssl_tls.c:3986: mbedtls_ssl_fetch_input() returned -26624 (-0x6800)
mbedtls/library/ssl_tls.c:3901: mbedtls_ssl_read_record_layer() returned -26624 (-0x6800)
mbedtls/library/ssl_cli.c:1540: mbedtls_ssl_read_record() returned -26624 (-0x6800)
0000059320 [comm.dtls] ERROR: handshake failed -6800
0000059321 [comm.protocol.handshake] ERROR: handshake failed with code 17
0000059322 [system] WARN: Cloud handshake failed, code=17
0000059572 [system] INFO: Cloud: disconnecting
0000059572 [system] TRACE: Close Attempt
    25.099 AT send      12 "AT+USOCL=0\r\n"
    25.140 AT read OK    6 "\r\nOK\r\n"
0000059613 [system] TRACE: socket_close()=success
0000059613 [system] INFO: Cloud: disconnected
0000060322 [system] INFO: Cloud: connecting
0000060322 [system] TRACE: sparkSocket Now =-1
0000060323 [system] INFO: Read Server Address = type:1,domain:$id.udp.particle.io
    25.851 AT send      56 "AT+UDNSRN=0,\"20003c000351353337353037.udp.particle.io\"\r\n"

I’d appreciate any kind of help to identify and eliminate those issues,…