SIM900 module not responding on hardware COM port - serial-port

I've got my sim900 module working with arduino by using their software serial library, however, I want to eliminate arduino from the equation and have serial communication directly to sim900 module.
I'm using putty as my terminal emulator. It's serial is configured to COM1 19200 8 N 1 the same as device manager configuration for this port.
I connect straight from hardware serial on my PCs motherboard into serial-to-ttl interface board which connects to sim900 module. The board has 4 pins - VCC GND TX RX. They're all connected to my sim900 hardware serial as follows: VCC=5V GND=GND TX=TX RX=RX (Yes I know that it's always actually TX=RX and RX=TX, but when I connect it that way my interface board doesn't blink any led to indicate a transfer whereas it does when I connect TX=TX and RX=RX). The switch on the module is set to hardware serial pins as well.
So the only thing that happens when I send AT commands such as AT or ATI and press enter is that puttys cursor comes back to the beginning of command that I typed. No response.
I'm thinking that I'm not doing something that the arduinos software serial port is doing when it sends commands to sim900.
Can anyone help please ? It's literally been days of trying different configurations with no results.
In that time besides getting sim900 working with arduino software serial I verified that the hardware serial port on my motherboard is working correctly and the interface board is working correctly as well.

Related

Sending Data from Arduino to Android using Bluetooth

I am trying to do a project based on arduino and Android in which I want to use ultrasonic sensors and Bluetooth module hc-05 . I want to detect any obstacle using ultrasonic and send it's distance to Android app using Bluetooth. I am completely new to arduino and have never used it before . How could I connect both the Bluetooth and ultrasonic sensor to arduino uno board without using breadboard? Is it possible to connect both of them without using breadboard and just the jumper wires?
You can connect the Bluetooth Module and Ultrasonic Sensor with jumper wires directly to the Arduino.
Depending upon the Ultrasonic Sensor you are interfacing, there must be a library or a sample code. You can tweak the code to get the distance in your desired format or variable.
As far as the Bluetooth is concerned, you can operate it at 3.3v or 5v depending upon the module you use. Most of the Bluetooth module support both 3.3v and 5v - as they have voltage regulators on their break out. I have used these and they work on 3.3v as well as 5v
For instance, check the Bluetooth HC - 05 Module in the below link :
http://www.amazon.in/Verve-VTA009-Bluetooth-Module-HC-05/dp/B00S15XTG8?tag=googinhydr18418-21&tag=googinkenshoo-21&ascsubtag=7a58e842-4c10-40bf-a48f-339edef372a7
For implementing the Bluetooth communication, prefer using the Software Serial. If you connect the Bluetooth HC 05's Rx and Tx to the Arduino's Hardware UART Pins, there can be unpredictable results. I have experienced that using HC05 with Software Serial is reliable. Additionally, you can use the Serial Monitor to debug your code at the same time. I mean, you can send the same data on Software Serial and the Serial port and check if things are as desired.
You can implement, the HC-05 Software Serial at 9600 baudrate. 9600 is the default baudrate on most HC 05 Modules.
For developing the Arduino code and testing it, you can use a terminal client like PuTTY on you computer. You need to establish a bluetooth connection between your computer and HC 05.
HC-05 runs at 3.3V, make sure you do level conversion from 5V to 3.3V using a zener diode. Or buy a level converter if you are new to electronics. If you don't, there is a good chance you will blow up the HC-05. If you could add a photo we can see if its already done on the Bluetooth module, then you need not worry about level conversion
HC-05 is basically a wireless serial port over bluetooh. On arduino create a software serial post using the library SoftwareSerial and send the sensor data to that serial port
There are libraries available for popular HC-SR04 ultrasonic sensor, if that is the sensor you are using.
For testing on android many app are availables like Bluetooh Terminal, you can receive the data sent from arduino.
Yes the whole project can be done without breadboard using connecting wires.

Arduino 2006 how to connect to my laptop?

I have borrowed an Arduino BT-V06 (analogue) from my college IT storage department.
At home I am trying to do some research on this for subsequent work I am going to perform with this Arduino later on. As this model is a 2006 version; my question is, how do I connect it to my laptop? Some sort of adapter? or perhaps shield it with a newer model that has a usb-port?
Because I would like to have it connected to my laptop in order to try out some codes on it.
Thank you very much for your time!
-M
There's at least two options. First, it's set up to be programmed over Bluetooth. So if you have Bluetooth on your laptop, you can connect the two wirelessly. Pins 0 and 1, per the documentation, are TTL serial transmit and receive pins (which are also used for Bluetooth communications), so if you AREN'T connecting via Bluetooth, you could connect a serial to USB adapter so you can connect to your laptop via USB. This reference has this to also say:
"The on-board serial communication between the bluetooth module and the Arduino sketch (running on the ATmega328) needs to be at 115200 baud (i.e. call Serial.begin(115200) in your setup() function). Communication between the bluetooth module and the computer can be at any baud rate.
Communication between the BT module and the computer can be temperamental. You might want to open the serial monitor a couple of seconds after resetting the board. The text of the Arduino getting started guide is licensed under a Creative Commons Attribution-ShareAlike 3.0 License. Code samples in the guide are released into the public domain."

Use debug serial pins to connect with a serial device on beaglebone rev c

I Have a RF module that communicate using serial port using RS232. It works in a normal computer.
I noticed that beaglebone has a serial debug slot and I tried to connect my device to it but, I can't send or receive messages using the serial debug slot.
If I connect the beaglebone to usb converting to RS232, I'll be able to communicate with my RF module. And I tested to connect by SSH using the serial slot and worked.
But I would like to use USB for another purpose. Is there a serial pins to be compatible with RS232?

Is it possible to use Arduino 2560's serial/USB communication without Arduino bootloader?

I have an Arduino 2560 and would like to send serial data to my PC. However, I am currently not using the Arduino Bootloader because I wanted to use a program that I wrote for an Atmega644 before (as far as I understood, one has to use the Arduino language when using the Bootloader?).
Does anyone know if what I am trying to do is possible with reasonable effort?
Connection to PC via 2560's serial0 does not depend on bootloader (if you plan connection when main program is running). You need 16u2 running to bridge 5V serial UART to USB or you can of course use any other option (e.g. MAX232 or so) to convert 5V UART to USB or RS232. But in case of RS232 double check baud rate error because of 16MHz crystal for particular baudrate.
2560 bootloader just implements firmware flash.

What happen when use rs232 instead of usb in arduino?

I just start a project which is very basic actually. But I need an information. It is about arduino serial communication. Here is the question.
If I connect arduino to computer using TTL to RS232 converter without USB cable then can I still use serial monitor to get some data or what happens ? Assume arduino is programmed before using usb cable, and it is powered externally when usb is not used.
for instance the code just
Serial.println("It is working");
delay(1000);
Thansk a lot.
you will fry it. Standard RS232 use a +-12V level, while arduino use TTL level (0-5V), so you still need a RS232 -> RS232TTL converter. If you use it, then using virtual serial over USB or real hardware serial is exactly the same, except that hardware serial port never appear/disappear when you plug in the arduino (there is not something like plug'n'play in rs232, it is always plugged)

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