HL7802 - KHTTP_ERROR: 1,5 over GSM

IoT Modules HL78
1

Hello,

I’m facing a problem using modem HL7802 with firmware 4.6.9.4.
I use only HTTP connection.

The connection to the serveur works fine when the modem is connected in CAT-M1 but when I’m in GSM (2G) I have the error: “HTTP connection error due to internal trouble”

Log MCU to HL7802
(10:11:06.946) AT+KCNXTIMER=1,30,2,60,0
(10:11:12.351) AT+KHTTPCFG=1,"my_serveur.com",80


Log HL7802
(2025-10-06 10:11:12.366) +KHTTPCFG: 1
(2025-10-06 10:11:16.027) OK
(2025-10-06 10:11:16.027) +KCNX_IND: 1,4,1
(2025-10-06 10:11:16.027) +KCNX_IND: 1,2,1,2,30
(2025-10-06 10:11:46.023) +KCNX_IND: 1,4,2
(2025-10-06 10:11:47.621) +KCNX_IND: 1,2,2,2,30
(2025-10-06 10:11:47.621) +KHTTP_ERROR: 1,5

How can I do to avoid this problem ?

Any help is appreciated :slight_smile:

2

How about tcp and udp?

I remember it should work in gsm mode

3

Hi,

Thanks for feddback.
I try another thing but I got an error:

(14:52:35.331) at+ksrat?
  (14:52:35.378) at+ksrat?
  (14:52:35.378) +KSRAT: 2
(14:52:35.378) OK
(14:52:42.974) at+cfun=1,1
  (14:52:43.025) at+cfun=1,1
  (14:52:46.798) OK
(14:52:55.927) at+cgdcont?
  (14:52:55.977) at+cgdcont?
  (14:53:04.337) +CGDCONT: 1,"IP",,,0,0,0,0,0,,0,,,,,
  (14:53:04.337) +CGDCONT: 2,"IPV4V6",,,0,0,0,0,0,,0,,,,,
  (14:53:04.337) OK
(14:53:15.542) at+cgdcont=1,"IP","hkcsl"
  (14:53:15.671) at+cgdcont=1,"IP","hkcsl"
  (14:53:15.671) OK
(14:53:17.655) at+cgdcont=1,"IP","hkcsl"
  (14:53:17.750) at+cgdcont=1,"IP","hkcsl"
  (14:53:17.750) OK
(14:53:27.966) at+cgpaddr=1
  (14:53:28.074) at+cgpaddr=1
  (14:53:28.074) +CGPADDR: 1
  (14:53:28.074) OK
(14:53:38.250) at+creg?
  (14:53:38.350) at+creg?
  (14:53:38.350) +CREG: 0,5
  (14:53:38.350) OK
(14:53:50.712) at+cclk?
  (14:53:50.823) at+cclk?
  (14:53:50.823) +CCLK: "25/10/06,14:53:46+08"
  (14:53:50.823) OK
(14:54:00.139) at+cgdcont?
  (14:54:00.245) at+cgdcont?
  (14:54:00.245) +CGDCONT: 1,"IP","hkcsl",,0,0,,0,,,,,,,,
  (14:54:00.245) +CGDCONT: 2,"IPV4V6",,,0,0,0,0,0,,0,,,,,
  (14:54:00.245) OK
(14:54:33.255) AT+KHTTPCFG=1,"google.com",80
  (14:54:33.383) AT+KHTTPCFG=1,"google.com",80
  (14:54:33.383) +KHTTPCFG: 1
  (14:54:34.778) OK
  (14:54:34.778) +KCNX_IND: 1,4,1
  (14:54:34.778) +KCNX_IND: 1,2,1,2,30
  (14:55:04.781) +KCNX_IND: 1,4,2 
  (14:55:06.300) +KCNX_IND: 1,2,2,2,30
  (14:55:06.300) +KHTTP_ERROR: 1,5

Is something missing to do especially if I’m in GSM ?

4

I think you use the wrong apn for +cgdcont

Btw, how about trying tcp and udp?

5

Hi,

Since I have put AT+KCNXCFG=1,“GPRS”,“good APN” it’s now working.
Now, even if I power OFF then power ON the board, it’s still working (without entering command KCNXCFG)

In the AT command I can see this (my developement started with module fw version 4.3.9):

image
image1296×484 74.2 KB

The modem shall works even if the command is not entred.

Btw, I now have to find a way to know precisely how to fix it.
To try to reset the modul I have dowloaded the firmware 4.3.9.0 and it’s still working.
How can I do to restart the module from scratch ?

6

Isn’t that the root cause is wrong APN is entered?