Why are there two COM ports after connecting the Bluetooth HC-05 module to my PC running on WIN10?
See this image from device manager:
For sending data I use only one of them but I have to check it before which is correct. I have no idea what the second is used for.
Any idea?
Related
I am trying to connect a WiFi module (ESP8266) to a "funduino" development board (Arduino Nano) but I have no success. Since I tried so much schematics I've found on the internet about the connection between them two, I kindly ask here if is anyone who succeed in "pairing" this two devices.
I am asking for the schematic and a functional source code.
Regards
The ESP-01 by default comes with nonOS SDK bootloader that communicated via AT commands, you can find the complete command set from Expressif here. This is designed for an MCU (like Arduino Nano) to use it purely as an WiFi module rather than using it as a stand-alone MCU (for which it will require NodeMCU SDK).
If you ever upload an Arduino sketch up to the ESP-01, it will erase the AT Command firmware.
Assuming your ESP-01 is still having the AT Command firmware. What #Ben provided is a sketch that allows you to type AT commands via the Serial Monitor to internact with the ESP-01, it is manual, and good for testing if ESP-01 is working (you type AT and press return on Serial Monitor, the ESP-01 will ack with Ok) but not practical as a real application. The minimum commands required to established an WiFi connection with ESP-01 is listed below.
AT+CIPMUX=1 - Enable single (0) or multiple connection (1) to the web server.
Multiple connection is a good option if you are repeatedly sending
out or reading data from the Internet.
AT+CWMODE=3 - Set WiFi mode: 1 is station mode (ESP8266 is client), 2 is AP mode
(ESP8266 acts like a WiFi router where your phone or PC can connect),
3 is AP+station mode (make the ESP8266 do both)
AT+CWJAP=“<your-ssid>”,”<your-pw>” - Connect to your WiFi. Provide your SSID name
and password inside the double qoutes.
AT+CIFSR - This returns the IP address of the module, indicating that it has
successfully connected to your WiFi router.
Once the WiFi connection is established, you can further communicate with the ESP-01 via the connection, like accessing a website for example:
AT+CIPSTART=0,"TCP", "www.example.com","80” - Start TCP or UDP connection. The
0 is the id of the connection.
AT+CIPSEND=0,16 - Command to tell the module data is ready to be sent. 0 is the
connection id, and 16 is the length of the data to be sent.
After this command, the ESP8266 will reply with the “>”
character to tell us that it will be waiting for the data to be
sent. If successful, the module will reply with “SEND OK”
GET / HTTP/1.1 - Send the http header, and other data, etc...
You can write your own sketch to automate those AT commands for interacting with with ESP-01 once you understand the AT commands required for establish a WiFi connection.
Here are two resources that I personally found extremely useful for doing more than connecting to WiFi.
STM32-ESP-01 Web Server - although this is for interfacing with STM32, the main difference is the pin assignment, so you should be able to port to Arduino easily.
MQTT via ESP-01
As for hardware interface, please noted that what #Ben provided is correct in principle, but you need to be aware that the ESP-01(ESP8266 to be precise) is a 3V3 MCU, so the connection is depended on what kind of host board you are using. If you are using Arduino Uno/Nano, both are having a 5V MCU, you will need a voltage divider (two resistors to drop the voltage to 3v3 before connecting to ESP-01) or a level shifter chip at least for the ESP-01 Rx pin to avoid the potential damage to the ESP-01.
I have two bluetooth HC-6 module and two Arduino UNO board. I want to connect these two arduino module using these bluetooth module. Can i connect?
HC-06 is a Slave only device, which means that you can connect your smartphone to it to send and get data, but itself can not act as a Master. You need at least one module that can act as Master, such as HC-05.
Note that HC-06 looks physically just like the HC-05, and not necessairly cheaper, I believe.
One connected to a HC-05 zs-040 and one connected to a HC-06 zs-040.
The HC-05 has a connection from pin 34 to +3.3v. This activates “full” AT mode.
enter image description here
I want to know how can i use 2 GSM Modems in one computer (using Windows) ?
Those modem have a usb connector but the system plug them as Mobile Modem in COM Port.
The probleme is how to use 2 Modems togeteher in different ports.
The modem reference is ls100 and it made by Lonsai i connected 2 modems in my computuer but in devices manager i found the COM Port of the first one that i put. did some one have an idea how to detect 2 COM Ports ?
Thank you.
If you are using serial port then that is not possible ofcourse. However, if you are using USB to connect the modem, you can use different COM ports. Here are some steps you can try and debug the issue:
Please refresh your device manager settings and see if you can find another COM port.
Plug in the modems one by one to see if the COM Port appears for both. Note what number has been assigned to each modem.
Try using different USB ports on your PC.
Try using a different terminal to see the COM Ports or multiple terminals for each modem
I've been trying to test a FT201XQ USB-I2C breakout board: UMFT201XB-01, so I can connect it to a master device such as an Arduino and sniff what that device is sending through I2C.
To see the output of the slave device I have successfully configured a Virtual COM PORT by installing the D2XX drivers provided by ftdchip.com. I can open the serial port through puTTY and everything seems fine in that regard.
Then, i've loaded the "master_writer" example on my Arduino, which sends 1 byte at a time to an address (0x22 is specified in the UM201XB-01 datasheet as the default address).
Nothing seems to happen in the COM port that i've earlier opened. Do I need to configure/program the FTDI device in some way? In that case, how can I do it, in a general way?
UMFT201XB-01 board http://www.ftdichip.com/Support/Documents/DataSheets/Modules/DS_UMFT201_220_230XB.pdf
Thank you in advance, and sorry if this is a "noob" question : P
I am using RXTX with Java to connect to serial port. But now i have to test whether the communication is working properly or not? How to do this. Do i need modem or can we test any way in my local with out modem.
this is the program i want to test http://rxtx.qbang.org/wiki/index.php/Two_way_communcation_with_the_serial_port
On Windows you can use a 'null modem emulator' called com0com. This registers 2 dummy com ports onto the OS, which will communicate between each other.
So, you'd need to connect to it 'twice', one for each end of the serial connection.
com0com also has variants called com2tcp & hub4com, if that's more appropriate for you.
HTH
Uh, no you don't need a modem(?). You can use a null modem serial cable to do loopback testing from one COM port to another. You can do this on a single PC or two different computers. If you don't have enough COM ports, use a USB to serial converter.