C# port.write(ENQ), scale turn off and receive null -

i try connect scale via rs232 cable. when try write "enq" port scale turn off , receive nothing. code. sorry bad english :(

class scalecas {             private serialport port = new serialport("com4", 9600, parity.none, 8, stopbits.one);              public string result = null;              public scalecas()             {                 port.datareceived += new serialdatareceivedeventhandler(port_datareceived);                 port.open();             }              private void port_datareceived(object sender, serialdatareceivedeventargs e)             {                 this.result = port.readexisting();             } } 

add

in class try write port

scale.port.write("enq"); console.write(scale.result); 

you not waiting scale answer, read value of result way lot faster filled data.

a way communicate using serialport readline , writeline, check out newline set correctly according device programming manual (which nice add question if asking question specific device).

some general troubleshooting of rs232 communications:

• check baud rate , other serial port configuration
• check eol (end of line) character, , use terminate writing statements , know how stop reading input messages (or use readline , writeline)
• check communication manually using teraterm or other serial terminal