SIM808 EVB-v3.2 / AT reply with whatever I'm sending / DB No Resp

Hey everyone,

I bought SIM808 (EVB-v3.2) and I’m trying to use it with the Arduino UNO using the AT commands,
I still didn’t insert any simcard into the sim 808, but i was just trying to get the AT commands working

I’ve connected the following :

TXD => Pin 4 on Arduino
RXD => Pin 5 on Arduino
GND => GND
VMCV => 3.7 V on Arduino

then I’ve uploaded the example of simple GPS read to the Arduino

#include "SIM900.h"
#include <SoftwareSerial.h>
//#include "inetGSM.h"
//#include "sms.h"
//#include "call.h"
#include "gps.h"

//To change pins for Software Serial, use the two lines in GSM.cpp.

//GSM Shield for Arduino
//www.open-electronics.org
//this code is based on the example of Arduino Labs.

//Simple sketch to start a connection as client.

//InetGSM inet;
//CallGSM call;
//SMSGSM sms;
GPSGSM gps;

char lon[15];
char lat[15];
char alt[15];
char time[20];
char vel[15];
char msg1[5];
char msg2[5];

char stat;
char inSerial[20];
int i=0;
boolean started=false;

void setup()
{
     //Serial connection.
     Serial.begin(9600);
     Serial.println("GSM Shield testing.");
     //Start configuration of shield with baudrate.
     //For http uses is raccomanded to use 4800 or slower.
     if (gsm.begin(2400)) {
          Serial.println("\nstatus=READY");
          gsm.forceON();	//To ensure that SIM908 is not only in charge mode
          started=true;
     } else Serial.println("\nstatus=IDLE");

     if(started) {
          //GPS attach
          if (gps.attachGPS())
               Serial.println("status=GPSREADY");
          else Serial.println("status=ERROR");

          delay(20000);	//Time for fixing
          stat=gps.getStat();
          if(stat==1)
               Serial.println("NOT FIXED");
          else if(stat==0)
               Serial.println("GPS OFF");
          else if(stat==2)
               Serial.println("2D FIXED");
          else if(stat==3)
               Serial.println("3D FIXED");
          delay(5000);
          //Get data from GPS
          gps.getPar(lon,lat,alt,time,vel);
          Serial.println(lon);
          Serial.println(lat);
          Serial.println(alt);
          Serial.println(time);
          Serial.println(vel);
     }
};

void loop()
{
     //Read for new byte on serial hardware,
     //and write them on NewSoftSerial.
     serialhwread();
     //Read for new byte on NewSoftSerial.
     serialswread();
};

void serialhwread()
{
     i=0;
     if (Serial.available() > 0) {
          while (Serial.available() > 0) {
               inSerial[i]=(Serial.read());
               delay(10);
               i++;
          }

          inSerial[i]='\0';
          if(!strcmp(inSerial,"/END")) {
               Serial.println("_");
               inSerial[0]=0x1a;
               inSerial[1]='\0';
               gsm.SimpleWriteln(inSerial);
          }
          //Send a saved AT command using serial port.
          if(!strcmp(inSerial,"TEST")) {
//      Serial.println("BATTERY TEST 1");
//      gps.getBattInf(msg1,msg2);
//      Serial.println(msg1);
//      Serial.println(msg2);
//      Serial.println("BATTERY TEST 2");
//      gps.getBattTVol(msg1);
//      Serial.println(msg1);
               stat=gps.getStat();
               if(stat==1)
                    Serial.println("NOT FIXED");
               else if(stat==0)
                    Serial.println("GPS OFF");
               else if(stat==2)
                    Serial.println("2D FIXED");
               else if(stat==3)
                    Serial.println("3D FIXED");
          }
          //Read last message saved.
          if(!strcmp(inSerial,"MSG")) {
               Serial.println(msg1);
          } else {
               Serial.println(inSerial);
               gsm.SimpleWriteln(inSerial);
          }
          inSerial[0]='\0';
     }
}

void serialswread()
{
     gsm.SimpleRead();
}

I keep on getting “DB : No Resp”
I tried to connect it using FTDI and then open a serial connection to test the AT commands, I sent the command “AT” and got response as “AT” (I was expecting OK) and then whatever I send I get it back as the same

Where am i going wrong ? is there anything needs to be done ?

Here’s the link to the board I’ve bought :

http://www.amazon.com/DIYmall-Development-Antenna-Arduino-Raspberry/dp/B016U7BI6G/ref=sr_1_2?ie=UTF8&qid=1454874046&sr=8-2&keywords=sim808

Thank you so much in advanced.

I keep on getting "DB : No Resp"

From what? Where? Nothing in the code you posted generates that message.

Links to the libraries you are using would be good.

where i can download the libraries of program?

Hi I found this:

https://www.adrive.com/public/P7QRkq/FZ1735-SIM808%20大V3.1.rar

It has a lot of information about this module, good luck.

And you can get it here:

https://es.aliexpress.com/store/product/5pcs-lot-SIM908-Module-GSM-GPRS-GPS-Development-Board-IPX-SMA-with-GPS-Antenna-for-Arduino/406986_32477424514.html

regards !!!

I have the same problem.

I tried to download the driver from the link, but is two dyas is always busy.

It is not possible attach the file.

Thanks

Adafruit have very nice tutorial and library which works with SIMCOM versions. Have a look on following link.

killer-souls:
I tried to connect it using FTDI and then open a serial connection to test the AT commands, I sent the command "AT" and got response as "AT" (I was expecting OK) and then whatever I send I get it back as the same

Where am i going wrong ? is there anything needs to be done ?

This is very much the correct way to test the board.

Be aware that the SIM808 has high power requirements, so you do NOT want to be using Vcc from the FTDI cable to the board.

The echoing you're getting is probably the command echo setting in your serial program.

The obvious things to try;

  1. Ensure you use a decent power supply for the SIM808
  2. remember to crossover the TX/RX.

Any progress on this? I'm using the same board with an Uno and can't get any sort of response whatsoever. I just want to send sms with it, possibly gprs. From the light pattern, it would seem that it is able to log in to the GSM network ok, so now why an't the arduino talk to it?

Also, what's the deal with TWO sets of RXD/TXT pins in yellow? Are these the ones we're supposed to connect up to the software serial ports for our sketch? Which set?

Any progress so far? I just bought the same boards.

I cannot find anywhere the datasheets. I found the schematic here:
https://www.scribd.com/document/336035473/SIM808-V3-1
but I don't have a scribd account so I cannot download it.

I don't understand what is the deal with the double RXD/TXD.

And one more thing: is the GPS PPS working? I don't get a PPS in the GPS LED.

HELP! I need the datasheet of this board.

Thanks.

Use this:

http://www.tuxti.com.br/arquivos/arduino/modulos/sim808/SIM808_manual.docx

http://www.tuxti.com.br/arquivos/arduino/modulos/sim808/SIM808_V3.1.rar

I managed to get this sending texts OK just by using code copied from David Watts you tube tutorial on SIM 800L. Had to change a few bits but was my first ever sketch. Used a Uno. Still having a few issues with getting it to do exactly what I want (send text at trigger of input) but working through it.
Powered the 808 off battery, used 3 wires on the yellow headers (row on "inside " of board)\