TTGO ESP32 + GSM 800l AT Commands - arduino

Question

Good day all
I'm working on a project that takes sensor data and sends it to an online database using HTTP requests.Im ussing the TTGO esp32 sim 800 board, Everything works fine and all the data is stored in my online database the problem is that I cant get the AT commands to work, I need the Signal strength, battery voltage, and amount of Data available on the sim card.
Can someone please assist with this matter?
kind regards Hansie
Code
#include <HCSR04.h>
#define SOUND_SPEED 0.034
#define CM_TO_INCH 0.393701
// Set serial for debug console (to Serial Monitor, default speed 115200)
#define SerialMon Serial
// Set serial for AT commands (to SIM800 module)
#define SerialAT Serial1
// Configure TinyGSM library
#define TINY_GSM_MODEM_SIM800 // Modem is SIM800
#define TINY_GSM_RX_BUFFER 1024 // Set RX buffer to 1Kb
// Define the serial console for debug prints, if needed
//#define DUMP_AT_COMMANDS
#include <Wire.h>
#include <TinyGsmClient.h>
#define uS_TO_S_FACTOR 1000000UL /* Conversion factor for micro seconds to seconds */
#define TIME_TO_SLEEP 36 /* Time ESP32 will go to sleep (in seconds) 3600 seconds = 1 hour */
#define IP5306_ADDR 0x75
#define IP5306_REG_SYS_CTL0 0x00
// TTGO T-Call pins
#define MODEM_RST 5
#define MODEM_PWKEY 4
#define MODEM_POWER_ON 23
#define MODEM_TX 27
#define MODEM_RX 26
#define I2C_SDA 21
#define I2C_SCL 22
int deviceID=101;
const int trigPin = 5;
const int echoPin = 18;
//Calculation variable for depth
//define sound speed in cm/uS
long duration;
float distanceCm;
double damDepth =200;
// Your GPRS credentials
const char apn[] = "Vodacom APN"; // APN
const char gprsUser[] = ""; // GPRS User
const char gprsPass[] = ""; // GPRS Password
// SIM card PIN (leave empty, if not defined)
const char simPIN[] = "";
// Server details
const char server[] = "grow-with-pierre.com"; // domain name:
const char resource[] = "/post-data.php"; // resource path, for example: /post-data.php
const int port = 80; // server port number
// Keep this API Key value to be compatible with the PHP code
String apiKeyValue = "tPmAT5Ab3j7F9";
#ifdef DUMP_AT_COMMANDS
#include <StreamDebugger.h>
StreamDebugger debugger(SerialAT, SerialMon);
TinyGsm modem(debugger);
#else
TinyGsm modem(SerialAT);
#endif
// I2C for SIM800 (to keep it running when powered from battery)
TwoWire I2CPower = TwoWire(0);
// TinyGSM Client for Internet connection
TinyGsmClient client(modem);
bool setPowerBoostKeepOn(int en)
{
I2CPower.beginTransmission(IP5306_ADDR);
I2CPower.write(IP5306_REG_SYS_CTL0);
if (en)
{
I2CPower.write(0x37); // Set bit1: 1 enable 0 disable boost keep on
} else
{
I2CPower.write(0x35); // 0x37 is default reg value
}
return I2CPower.endTransmission() == 0;
}
void setup()
{
Serial.begin(115200); // Starts the serial communication
pinMode(trigPin, OUTPUT); // Sets the trigPin as an Output
pinMode(echoPin, INPUT); // Sets the echoPin as an Input
// Set serial monitor debugging window baud rate to 115200
SerialMon.begin(115200);
// Start I2C communication
I2CPower.begin(I2C_SDA, I2C_SCL, 400000);
// Keep power when running from battery
bool isOk = setPowerBoostKeepOn(1);
SerialMon.println(String("IP5306 KeepOn ") + (isOk ? "OK" : "FAIL"));
// Set modem reset, enable, power pins
pinMode(MODEM_PWKEY, OUTPUT);
pinMode(MODEM_RST, OUTPUT);
pinMode(MODEM_POWER_ON, OUTPUT);
digitalWrite(MODEM_PWKEY, LOW);
digitalWrite(MODEM_RST, HIGH);
digitalWrite(MODEM_POWER_ON, HIGH);
// Set GSM module baud rate and UART pins
SerialAT.begin(115200, SERIAL_8N1, MODEM_RX, MODEM_TX);
delay(3000);
// Restart SIM800 module, it takes quite some time
// To skip it, call init() instead of restart()
SerialMon.println("Initializing modem...");
modem.restart();
// use modem.init() if you don't need the complete restart
// Unlock your SIM card with a PIN if needed
if (strlen(simPIN) && modem.getSimStatus() != 3 )
{
modem.simUnlock(simPIN);
}
// Configure the wake up source as timer wake up
esp_sleep_enable_timer_wakeup(TIME_TO_SLEEP * uS_TO_S_FACTOR);
}
void loop()
{
postData();
Serial.print(String(" Percentage: ") + depth());
// Put ESP32 into deep sleep mode (with timer wake up)
esp_deep_sleep_start();
}
String postData()
{
SerialMon.print("Connecting to APN: ");
SerialMon.print(apn);
if (!modem.gprsConnect(apn, gprsUser, gprsPass))
{
SerialMon.println(" fail");
}
else
{
SerialMon.println(" OK");
SerialMon.print("Connecting to ");
SerialMon.print(server);
if (!client.connect(server, port))
{
SerialMon.println(" fail");
}
else
{
SerialMon.println(" OK");
// Making an HTTP POST request
SerialMon.println("Performing HTTP POST request...");
String httpRequestData = "api_key=" + apiKeyValue + "&value1=" + String(deviceID)
+ "&value2=" + String(distanceCm) + "&value3=" + String(80) + "&value4=" + String(40) + ""+ "&value5=" + String(50) + "";
// then, use the httpRequestData variable below (for testing purposes without the BME280 sensor)
// String httpRequestData = "api_key=tPmAT5Ab3j7F9&value1=24.75&value2=49.54&value3=1005.14";
client.print(String("POST ") + resource + " HTTP/1.1\r\n");
client.print(String("Host: ") + server + "\r\n");
client.println("Connection: close");
client.println("Content-Type: application/x-www-form-urlencoded");
client.print("Content-Length: ");
client.println(httpRequestData.length());
client.println();
client.println(httpRequestData);
unsigned long timeout = millis();
while (client.connected() && millis() - timeout < 10000L)
{
// Print available data (HTTP response from server)
while (client.available())
{
char c = client.read();
SerialMon.print(c);
timeout = millis();
}
}
SerialMon.println();
// Close client and disconnect
client.stop();
SerialMon.println(F("Server disconnected"));
modem.gprsDisconnect();
SerialMon.println(F("GPRS disconnected"));
}
}
}
float depth() //Find Depth in cm
{
double persentage;
// Clears the trigPin
digitalWrite(trigPin, LOW);
delayMicroseconds(2);
// Sets the trigPin on HIGH state for 10 micro seconds
digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);
// Reads the echoPin, returns the sound wave travel time in microseconds
duration = pulseIn(echoPin, HIGH);
// Calculate the distance
distanceCm = duration * SOUND_SPEED/2;
// Prints the distance in the Serial Monitor
Serial.print("Distance (cm): ");
Serial.println(distanceCm);
persentage = (distanceCm/damDepth)*100;
if(persentage>=100)
{
persentage=100;
}
else
{
persentage=100- persentage;
}
return persentage;
}

Answer 1

For at least some of the desired functions, it isn't necessary to push AT-commands.
Try signalStrength = modem.getSignalQuality(); instead. It works for me on the Lilygo T-Call SIM800L. You can check out TinyGSM's Github-page for additional commands or this handy class reference