Sim800l not connecting to network


#1

Hi,
I am using sim800l module, first my aim is to connect and register to network. But module always looping and printing following data,
RDY
+CFUN: 1
+CPIN: READY
Call Ready
SMS Ready
Simple code like below,
#include <sim800l.h>
#include <softwareserial.h>
void setup()
{
Serial.begin(9600);
GSM.begin(38400);
}
void loop()
{
Serial.println(GSM.readGSM());//just read function nothing else
}
Please help me to connect a network.
I am confused with AT+COPS=1,1,“MYNETWORK” and AT+CREG=1. How to use these commands to lock particular network.


#2

I think your module is getting restarted, Make sure you have given 2A capable power supply. Module needs 4V, 2A for operation.
AT+COPS (CHECK OPERATORS)command is used for checking which network operators are available and possibly connect to any selected one.

AT+CREG is for checking network registration status, You should get +CREG: 0,1 +CREG: 0,5 for valid network connection


#3

Hi,
I tried with 4.4V 2Amps battery still i am facing this loop issue. Any help. And how to know SIM800L is TTL Logic or RS232 Logic.


#4

Share your circuit photo. Make sure you are using short wire for connecting to batteries. 4.4V is too high. It will cause OVER_VOLTAGE_POWERDOWN . It should be between 3.7V to 4.2V max.

SIM800L are having 2.8V logic by default. If you have a level translator in between for conversion to RS232 level like MAX232 then you can say your module accepts RS232 levels.


#5

This is my simple image


#6

Blinking for a second and printing on console,
RDY
+CFUN: 1
+CPIN: READY
Call Ready
SMS Ready
and after 3 to 4 seconds gap again starting blinking with 1 second gap with same console data.


#7

Its definitely restarting. Keep battery voltage below 4.4V as i mentioned. 4.4V will make it restart.
Measure voltage on battery terminals.
By picture i meant exact photograph of your connections.


#8

Here is my kit picture, i thought signal weak so soldered aluminum plate to antenna.


#9

Can you make the wire shorter and try , From battery to module?
And make sure your module has level translator on it. Otherwise 5V from TX RX of arduino will damage module.


#10

can you please share if you have any idea of level translator circuit for arduino to SIMI800L.


#11


The circuit for level translator is given in the datasheet or the hardware design guide for SIM800. Please refer it. There are other level translator chips also available like, TXS0104, TXS0102 etc


#12

Might be some power issues, but I fixed mine by just trying some AT command

AT+CBAND?

Then, AT+CBAND=“DCS_MODE”

That works for me. Give it a try man.


#14

Hi Dhawal,
Glad you liked it . :slight_smile:
Please create separate posts on different topics. So that this and the new discussion stays clean.


#15

Thank you for your response and sorry for misplacement. will create a new thread