Portenta H7 with Cat. M1/NB shield does not connect over LTE Cat-M1 | Telit Cinterion IoT Developer Community
June 30, 2022 - 1:40pm, 567 views
While working with the Arduino Portenta H7 Cat. M1/NB shield, I found out that the Thales Cinterion TX62 cellular modem only connects over NB-IoT, NOT over LTE Cat-M1.
I'm using th Arduino Portenta library, with the below code snippet:
#include <GSM.h>
char pin[] = SECRET_PIN; //example "1234"
char apn[] = SECRET_APN; //example "live.provider.com"
char username[] = SECRET_USERNAME;
char pass[] = SECRET_PASSWORD;
void setup() {
Serial.begin(115200);
while(!Serial) {}
GSM.debug(Serial);
if(GSM.begin(pin, apn, username, pass, CATM1)){
Serial.println("connected");
}
}
I defined the use of CATM1 in the GSM.begin()
, but it doesn't connect and eventually moves to NB-IoT after a few tries, as shown in the logs:
AT^SXRAT=7
+CME ERROR: unknown
AT error code 0
CellularContext connect
Setup SIM (timeout 10000 ms)
...
+CEREG: 2<cr><ln><cr><ln>+CEREG: 5,"2D5B","0187FB66",9
Any pointers on how to make the shield connect over LTE CAT-M1?
I haven't managed to directly communicate with the cellular modem yet, allowing me to send AT Commands to the board directly. Any support to make this work would also be appreciated.
Thanks,
Laurens
Hello,
Are you sure that this SIM should work in LTE Cat-M1? Please check the available networks with AT+COPS=? And also check AT+CGDCONT?, make sure that you use the right APN and delete the other entries. It should be possible to set AT^SXRAT=7, please check the current setting with AT^SXRAT?, reboot the module and try again. Please also check AT^SCFG? output to verify the bands enabled.
I suppose that you should get the board documentation from Arduino. I'll try to find some documentation regarding your question.
Best regards,
Bartłomiej
Thanks for the support. Turned out that the Cat M1 bands were disabled:
Which was solved after entering the following command (8000 is for B20):
For reference, below the Arduino code to directly communicate from your PC to the Cinterion TX62 modem.
Thank you for the feedback.
Great that the code was helpful.
BR,
Bartłomiej