HL7800M returning various +CEREG: 2 after wake up without request

IoT Modules Legacy HL Series
1

Hello,

We use a HL7800M, over uart, version HL7800-M.4.6.9.4.

This issue is starting happening more often: After waking/powering up the HL7800M, it returns various and random +CEREG: 2, +CEREG: 0, +CEREG: 5, without sending any at command to it.

The module was previously registered and working fine, then after a power cycle or Sleep/wake cycle, before sending any at command to it, it returns these responses unexpected and randomly:
+CEREG: 2
+CEREG: 2
+CEREG: 0
+CEREG: 2
+CEREG: 2
+CEREG: 0

Only reflashing the HL this issue is solved

Regards

2

Update:
Reflashing does not solve the issue
Happens also when communicating through USB comm port:

ati3
HL7800-M.4.6.9.4

OK
at+cfun=1,1
OK

+CEREG: 0

+CEREG: 2

+CEREG: 0

+CEREG: 2

+CEREG: 0

+CEREG: 2

+CEREG: 3

+CEREG: 2

+CEREG: 3

+CEREG: 2

+CEREG: 3

+CEREG: 2

+CEREG: 3

+CME ERROR: 4

HL7800-M.4.6.9.4

OK

HL7800-M.4.6.9
HL78xx.4.6.9.4.RK_02_01_02_00_137.20210615
2021/06/15 21:02:09
IMEI-SV: 3503908299592314
Legato RTOS: 18.09.6.ALT1250.rc8 2021/05/18 20:22:09
atSwi: 44.01
UBOOT: 01.03
Apps: RKAPP_02_01_02_00_120__c2a0a2a6e5dd44ea4710b32fe98e69dc72bab7ce
MAC: ALT1250_02_01_02_00_123_FW
PHY: 12.50.265649
PMP: 277291
SBUB: 1
SBFW: 1
RPuK: 53F7A48A
FPuK: 139A8E70
RBUB: 0
RBFW: 0

AT&F0
+CME ERROR: 4
AT&V
ACTIVE PROFILE:
E1 Q0 V1 X4 &C1 &D1 &R1 &S0 +IFC=2,2 &K3 +IPR=115200 +FCLASS0
S00:0 S01:0 S03:13 S04:10 S05:8 S07:255 S08:0 S10:1
STORED PROFILE 0:
E0 Q0 V1 X4 &C1 &D1 &R1 &S0 +IFC=2,2 &K3 +IPR=115200 +FCLASS0
S00:0 S01:0 S03:13 S04:10 S05:8 S07:255 S08:0 S10:1
STORED PROFILE 1:
E1 Q0 V1 X4 &C1 &D1 &R1 &S0 +IFC=2,2 &K3 +IPR=115200 +FCLASS0
S00:0 S01:0 S03:13 S04:10 S05:8 S07:255 S08:0 S10:1

OK

3

Hi @jgaston ,
According to your description, I have two concerns regarding your issue:

  1. Your issue is that after wake up/power up the HL7800M module, it returns unexpected variables +CEREG:2, +CEREG:0 and you want to know how to disable these URC, don’t you?
  2. Or after the HL7800M module wake up/power up, it can’t connect to the network and you want to know why it is?

Thanks,

4

Hi,
I know how to disable them by at+cereg=0 and at+creg=0. But sometimes they come back again.

I want to know in what conditions, after a wakeup, the radio would send these strings:
Is it trying to register?
Is it a bug?
Is “+CEREG: X” a response our host should expect at any point of the communication?

Thanks