I have seen several articles and videos showing how to use COM O COM Serial Port Emulator to send on one COM port and receive on another. But in my case I have to send on one ports and I also receive on the same port. Can COM O COM software do that?
I cannot find any other place to ask the question.
Hmm a bit weird question. What's the point in reading what you just wrote?
If you want to send and receive on the same port the only way is to phisically loop (wire up) TX and RX on the serial port and send and receive on it.
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Currently I have a server, that communicates with a projector through a RS232. The server opens a com port when the projector is connected. The same happens to any PC when a certain type of device is connected through the USB (lets say an Arduino for example). What I want to do it basically replace the projector with a PC/Arduino/Raspberry without the server noticing anything. That would mean the server will recognise the connected PC and open a COM port for it. What do I need to do on the PC so that it automatically opens a com port on the server? I guess there is something very basic that any printer, Arduino, projector etc does, that computers recognise it as a "com port device".
P.S. Doesn't matter the OS on the PC, I just need to make it work and then implement w/e I need to do with the established communication over the port.
P.S.2 I've searched a lot about it, but probabl I am doing it wrong, because I didn't find my type of question anywhere.
COM ports are basically hardware that is detected by the system. Let's say, if an Arduino is connected to a PC, it has its onboard USB to TTL converter which can be found in the device manager(if using windows). Similar USB to TTL converters are there in the market like CP2102, PL2303 which acts like a COM port even if no device is connected further to it. it may be possible that the program you are using(as you referred server) may be sending some data over the serial port and verifying the hardware.
What you need to do to replace it is, first of all, find the baud rate at which the communication is going on, then, listen over the serial lines which machine is sending which message in the sequence(there must be a handshake as I mentioned earlier), if a complicated algorithm is not used by the device, you can simply mimic the device by sending same messages over serial.
I am trying to read BLE telegrams sent to a usb plugged reciever to my PC.
I am using a serial port reader ( used putty at first then tryed some other software from the net). However, I get nothing, not data at all sent; not from my sender not even any telegram from may be other unknowm devices that may be there advertising.
I have run mode on command line to give me information and it shows that my com port has a baudrate of 1200.
I must say this value was not fix it goes from 1200 to 57600.
I know that my data is sent at a baudrate of 57600: so I'm thinking may be the problem is that the baudrates being different it can't get the data but then it should come to a time where I can see at least some insignificant data of incomplete telegram. I have also tried to change the baudrate on the serial com port reader but same result nothing at all.
My question is what might be the problem and how can I fix it ? in other words having a BLE reciever and tranciever how can I read the telegrams on COM ports
I want to know some general communication strategies, which should be followed for a communication via COM (serial) Port.
I can read/write at the port, also can list all the available ports on the machine. I'm using Qt C++ with QSerialDevice. For testing on a windows machine with no physical serial port, I'm using VPSE (virtual port)
Typical Flow (assumed):
List all the available serial ports of the computer.
Find out at which port my device (micro-controller) is connected - how to do it?
Device found.
Start a thread for reading from the port, another thread for writing it.
Safely close connection
Finding out at which port the device is connected sounds challenging to me. How to achieve it? I guess, I will send a HELLO message to each ports, if my device replies a specific per-defined reply message I can be sure my device is connected at that port. Can I?
Also I think, to seperate threads are necessary because at any time I may receive message from the Micro-controller device.
Thanks for helping :)
I'm creating a simple device that sends data to a Windows PC over serial COM ports.
I'd like the software to be able to scan the available COM ports until it recognizes the device. The problem is, if the PC tries to initiate the handshake with a device other than mine, it may interpret the commands [wrongly, of course].
The only solution I see is for my device to periodically broadcast some sort of identifier, perhaps 5 times per second or so, so the application only needs to listen for that identifier rather than risk corrupting another device also connected to a COM port. When the application loads, it listens on each available COM port until the device is recognised. Does this sound reasonable?
Thanks
IMO whatever the direction on which you initiate the handshake, the problem will be the same.
If you send your handshake from your device and another application on your PC is listening to the corresponding serial port, it also has risks to badly interpret the data you are sending.
So I would say that software on both side should be protected against incoherent data they receive from the outside.
I have the following scenario.
I have a LAN and more than one GSM modems are connected to a server. I want to receive incoming call on GSM modem and transfer this call to other PC on the network. Is it possible? Can anyone give me an idea to achieve this?
You cannot 'transfer the call'.
You will have to receive the calls from each modem on the server only, then you can implement something like a VOIP/sound streaming system by which you can simply send and receive the audio between server and client(s).