6 replies to this topic

[m.sainath]

using System.IO.Ports;using Microsoft.SPOT;using Microsoft.SPOT.Hardware;using SecretLabs.NETMF.Hardware;using SecretLabs.NETMF.Hardware.Netduino;namespace barcode_scanner{    public class Program    {        public static InputPort bsr = new InputPort(Pins.GPIO_PIN_D0, false, Port.ResistorMode.Disabled);        public static OutputPort led = new OutputPort(Pins.ONBOARD_LED, false);        public static void Main()        {            SerialPort mySerialPort = new SerialPort("COM1");            mySerialPort.BaudRate = 9600;            mySerialPort.Parity = Parity.None;            mySerialPort.StopBits = StopBits.One;            mySerialPort.DataBits = 8;            mySerialPort.Handshake = Handshake.None;            mySerialPort.DataReceived += new SerialDataReceivedEventHandler(DataReceivedHandler);        }        public static void DataReceivedHandler( object sender, SerialDataReceivedEventArgs e)        {            led.Write(true);            Thread.Sleep(1000);            led.Write(false);            Thread.Sleep(Timeout.Infinite);        }

 

[color=rgb(102,102,102);font-family:'Segoe UI', Helvetica, Garuda, Arial, sans-serif;]I'm using the above code to receive data through a serial port connected to my netduino plus 2 via a breakout board (RS232 to TTL converter- [/color]http://www.embeddedm...-TTL-Converter/[color=rgb(102,102,102);font-family:'Segoe UI', Helvetica, Garuda, Arial, sans-serif;]). The data i want to receive is from a barcode scanner whose output is a RS232 female, so i use a RS232 male to male cable and then use the above mentioned breakout board to connect to netduino plus 2. Upon use of the above code led does not blink. All i want to do is blink the led when data is read from barcode scanner i.e., when the barcode scanner scans a barcode. Please help me resolve this. Thanks in advance.[/color]

[NooM]

try:

 

SerialPort mySerialPort = new SerialPort("COM1", 9600);

 

remove all the other stuff like mySerialPort.Parity

(looks like its standard settings)

 

also add mySerialPort.Open();

 

and remove the Thread.Sleep(Timeout.Infinite);

from the event. instead add it after mySerialPort.Open();

[Kem]

Like NooM said on the Thread.Sleep(Timeout.Infinite);, but as far as I know you also have to read the data from the serial buffer, otherwise you will not receive new data.

 

You could also change the sleep of 1000 ms to a timer that will turn off the led after 1 second. This way you do not have to pause the thread.

[m.sainath]

using System;using System.Net;using System.Net.Sockets;using System.Threading;using System.IO.Ports;using Microsoft.SPOT;using Microsoft.SPOT.Hardware;using SecretLabs.NETMF.Hardware;using SecretLabs.NETMF.Hardware.Netduino;namespace barcode_scanner{    public class Program    {        public static InputPort bsr = new InputPort(Pins.GPIO_PIN_D0, false, Port.ResistorMode.Disabled);        public static OutputPort led = new OutputPort(Pins.ONBOARD_LED, false);        public static void Main()        {            // write your code here                        SerialPort mySerialPort = new SerialPort("COM1");            mySerialPort.BaudRate = 9600;                        mySerialPort.Open();            Thread.Sleep(Timeout.Infinite);            mySerialPort.DataReceived += new SerialDataReceivedEventHandler(DataReceivedHandler);                    }        public static void DataReceivedHandler( object sender, SerialDataReceivedEventArgs e)        {            led.Write(true);            Thread.Sleep(1000);            led.Write(false);        }    }} 

 

i get An unhandled exception of type 'System.InvalidOperationException' occurred in Microsoft.SPOT.Hardware.SerialPort.dll upon following the above changes.

[Nevyn]

Have you tried moving the Thread.Sleep(Timeout.Infinite) below the binding to the event handler for the serial port?

 

The code above as written will never bind to the event handler.

 

Regards,

Mark

[ziggurat29]

the bsr:

new InputPort(Pins.GPIO_PIN_D0

is causing that.  If you comment out line 15, you'll get past your exception.  The reason is that D0 and D1 are used by COM1, so the open fails because the pins are already in use for something else.

 

also, you'll never get to line 29 because of line 27.  reverse those.

 

you may wish to make your serial port object accessible outside the scope of main(), like you did with your led and bsr.  this isn't strictly required here because you can get to it from your event handler params.

 

also, I'm sure that the code in DataReceivedHandler is just for test, to blink a light when data comes in, but you'll shouldn't delay in that handler unless you like buffer overruns.  also you must consume (read) the data that is available, which is not happening in your code above.  you could possibly do something like:

 

public static void DataReceivedHandler(object sender, SerialDataReceivedEventArgs e){	//toggle lamp so we can see something happened	led.Write(!led.Read());	//consume (and discard) what is available	SerialPort mycerealport = (SerialPort) sender;	int nToRead = mycerealport.BytesToRead;	if ( nToRead > 0 )	//and really it always should be	{		byte[] buff = new byte[nToRead];		int nRead = mycerealport.Read(buff, 0, buff.Length);		//don't do anything with the data.  Or maybe we do!  send it back out!		mycerealport.Write(buff, 0, buff.Length);	}}

good luck!

[vicen.david@telefonica.net]

Hello,

 

Can you try with COM2 instead COM1.

 

Br.

 

David Asensio