Serial port connected event

Implementation of the SerialPort class is very straight-forward. To create an instance of the SerialPort class, you simply pass the SerialPort options to the constructor of the class.

Once you are ready to use the Serial Port, you will need to open it:. Now, we are ready to receive the data. However, to write this data to the TextBox on a form, we need to create a delegate. NET does not allow cross-thread action, so we need to use a delegate.

The delegate is used to write to the UI thread from a non-UI thread. We can now receive data from a serial port device and display it on a form. Some devices will send data without being prompted. Indicates that a non-data signal event has occurred on the port represented by the SerialPort object. Skip to main content. This browser is no longer supported. Download Microsoft Edge More info. Contents Exit focus mode.

Serial Port Class Reference Is this page helpful? Please rate your experience Yes No. Any additional feedback? Namespace: System. Ports Assembly: System.

Represents a serial port resource. In this article. SerialPort IContainer. SerialPort String. SerialPort String, Int SerialPort String, Int32, Parity. Gets a value indicating whether the component can raise an event.

Inherited from Component. Gets or sets the byte encoding for pre- and post-transmission conversion of text. Gets or sets the byte that replaces invalid bytes in a data stream when a parity error occurs. Gets or sets the port for communications, including but not limited to all available COM ports. CreateObjRef Type. Inherited from MarshalByRefObject. Dispose Boolean. Making use of this, you can fire up a thread which will continuously monitor the underlying receive buffer and only read when your desired number of bytes are present in the buffer.

To share the received data between the Serial Read Thread and main, the better way to do is to make use of queues. Based on FIFO principle, your Serial Read Thread will be the one responsible for the enqueue operation only and main will be responsible for dequeue operation only.

There won't be a case of data duplication etc. In main, you can decide how many bytes must be in this queue and only then you can dequeue. Stack Overflow for Teams — Collaborate and share knowledge with a private group.

Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Python Serial port event Ask Question. Asked 1 year, 6 months ago. Check the Handshake enumeration values I think it's safe to say there's not much "standard" about a PC Serial port. But, if you read the documentation for the DsrHolding member of the SerialPort class, it states Data Set Ready DSR signal is usually sent by a modem to a port to indicate that it is ready for data transmission or data reception.

That's the only use of the DSR pin. It is very common to the DSR to go low as soon as a device receives data to go high again when it's finished processing the data. This is normally not affected by how the flow control is set up. The fact that a device cannot accept data because it's busy is invariant--e. With a modem, a DSR going low could be extremely ephemeral; with other devices that could be quite lengthy.

I'm not sure what you mean by "SerialPort class doesn't support it", the serial port doesn't use that pin directly in that it won't stop you from trying to send data to a device that says it's not ready. I was probably overusing the "handshaking" term, at least in the context of SerialPort. This sometimes isn't driven until the DTR is asserted, which needs your port to be "opened".

As stated in an earlier response, this is Carrier Detect, meaning that the DCE has a communications channel available. You have to be able to talk to a modem to configure and connect dial before CD becomes true. It is usually accompanied by a "RING" string on the data lines, but if the serial port is powered down more likely on an embedded system than a PC the Ring can cause an event.

Other devices should have an equivalent NOP poll to respond to, or have hardware handshake.