I am trying to read serial port data through the Command prompt and "Serial Port Monitor" application.
I am using "Serial Port Monitor" for monitoring the serial port data. I am connected to the device using port COM3, but I am not getting any data in the Serial port Monitor application.
When I type "mode" in the command prompt, I am getting the below:
Status for device COM3: ----------------------- Baud: 19200 Parity: None Data Bits: 8 Stop Bits: 1 Timeout: OFF XON/XOFF: OFF CTS handshaking: OFF DSR handshaking: OFF DSR sensitivity: OFF DTR circuit: ON RTS circuit: ON
When I type "TYPE COM3", I am not getting any data in the command prompt also.
Can someone please let me know, what will be the issue.?
Related
I am trying to pragmatically control scanning operation of Gryphon I GPS4400 barcode scanner.
Scanner is attached to host over usb cable and scanner is programmed to act as virtual serial port.
I have control over serial port on host and I am receiving data from scanner regularly, also I am able to send some data to scanner over serial port. Scanner from my random text sent sometime response to serial port some time just beep.
I am trying to activate scanning mode:
Serial On Line: Scanning is initiated by command sent through the
host interface (manual triggering can be enabled in this read mode
through option setting).
(I know how to activate this mode on scanner, by reading configuration barcodes, but after that I do not know how to send command to trigger scanning)
My problem is that i can't find what sequence I need to send to scanner to start scanning?
Is it possible at all to control scanning by commands over virtual com port attached by USB or I need to have dedicated serial cable with special wiring ?
I wanted to test if my UART(ttyMT1) is working on my custom board (android project). I have 2 UARTs on my board- ttyMT0 & ttyMT1. UART ttymt0 is my debug port. I have microcom on my board as well.
Test1:
I connected Tx and Rx of ttyMT1 with a female to female jumper wire. Then, on my ADB, i opened microcom for ttyMT1 using the below command:
microcom -s 115200 /dev/ttyMT1
On my debug port (using minicom), ttyMT0, I transmitted to ttyMT1 using echo as shown :
echo -ne 'Hello' > /dev/ttyMT1
and i was able to get the transmitted data print (HELLO) on ttyMT1.
What i wanted to know was, is this enough to verify that my UART ttyMT1 is working fine or do i need to try something else?
Test2:
What i tried again was to connect ttyMT0 to my PC's usb port and ttyMT1 to another USB port of my PC using 2 separate USB to UART connectors. Then i opened 2 minicom, one for each and tried to transmit the same Hello from ttyMT0 to ttyMT1 (ttyMT0 shows as ttyUSB0 on my PC and ttyMT1 as ttyUSB1). But i didn't receive any print on ttyMT1. Why is that?.
p.s. I'm unable to type anything on ttyMT1. I probed ttyMT1 on Oscilloscope and i got the Tx signal but I didn't get anything on my scope when I probed on Rx.
I think you need to have SELinux permission to access serial port in android. However check this code here to read serial port : https://programmer.help/blogs/serial-port-operation-with-jni-method-under-android.html. It will require you JNI.
Trying to reverse an engineer a program that communicates with a device through a COM PORT. From monitoring the program, it sends 4 bytes of 0x00 and then the device replies back with the same and switches to flash mode. When I send the same bytes, the device does not respond, and in fact, no matter what I send, the serial port monitor says 0x00 is being written.
I've tried several different com port monitors, tried several different baud rates, flush com port before sending the command. Nothing seems to work. What could cause this type of issue?
no matter what I send, the serial port monitor says 0x00
From what you describe it seems like the serial sniffer you use is faulty.
Serial port sniffer I'm using successfully is this Serial Analyzer.
I've installed the Arduino virtual USB serial port driver, it's appeared as COM4 on my device manager. I double checked by listing all available serial ports in powershell
> [System.IO.Ports.SerialPort]::getportnames()
COM1
COM4
However, when I try to do an echo to the serial port, it says it does not exist
> echo helloworld > COM4
The system cannot find the file specified.
I am trying to upload some firmware in to my arduino, but I kept getting denied by the port. Trying a different USB gives me the same result. I wrote a small program to test the serial port and I get the error:
The serial port "COM4" does not exist.
The device name of a serial port on Windows is \\.\COMn where n is the port number. A device driver can emulate the DOS device name, like "COM4" if it chooses to do so, very simple to do in the device driver code. But that's an increasingly rare thing to do, especially for port numbers larger than 2 and extra especially for port numbers larger than 4. So seeing your echo command fail is not unusual.
A serial port cannot be shared, it can only be opened once by a process and everybody else that tries to open it will get the fail-whale ERROR_ACCESS_DENIED error code. Necessarily so, serial ports sit at the very bottom layer of the OSI model, there is no protocol that arbitrates access to the port. Or to put it another way, the operating system has no guidance on who should get the data that the port receives. There can be only one candidate, the process that opened the port first. So the error message you got is not unusual, you have to make sure that nobody else is using the port. Including the Arduino serial port monitor.
I am using a EVB for siemens MC45 GSM modem. Itried to send At commands to it via serial port with Hyperterminal in windows (both Xp and 7). But the hyperterminal window is showing that I am connected but when I type something it doesnot show my writings. and no response from the GSM modem is received.
What Can I do ?
The problem is with your hyper terminal settings when you are connecting with the modem.
Use these settings: Baud rate:9600 data bits:8 stop bits:1 parity bits: none flow control:none Should work now. Also check whether you are communicating with the correct port
Have you configured the hyperterminal session properly? I think you will probably need to set it up as follows:
BaudRate 19200
Databit 8
No Parity
Stopbit 1
No Flow control