Problem with Baudrate change-over after establishing connecting

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By SisyB , 24 December, 2018
Forums
Gurux.Serial

I am new to C#Sharp and i am developing a program to read or program energy meter via serial port.I connect to the meter at 300 baudrate and do initial handshake
At this stage i can connect to the meter after initial /?!<CR>LF> command.The problem i have is when i am attempting to send the ACK command together with baudrate change-over.
I am suppose to send this command(to the meter) withing 1.5s of receiving identification message from the meter and i can 'ACK' within the set limits but struggling with changing form 300 read mode(00) to 9600 (051) mode....."<ACK>051<CR>LF>"
i have tried to close the port (Comport.Close) and set new baud rate(Comport.Baudrate=9600) but it doesn't work.My code looks as below
ComPort.DiscardInBuffer(); // clearing buffer form Dump Mode
ComPort.RtsEnable = false;
ComPort.DtrEnable = false;
ComPort.Close();
await UseDelay();
//then set new settings
ComPort.BaudRate = 9600;// new baudrate
if (ComPort.IsOpen==false)
{
ComPort.DataReceived += new SerialDataReceivedEventHandler(DataReceived);
ComPort.Open(); }

await UseDelay();
ComPort.RtsEnable = true;
ComPort.DtrEnable = true;
byte[] ack = new byte[] {0X06,0X30,0X35,0x30,0X0D,0X0A};
//MessageBox.Show(DataReceived);
ComPort.Write(ack, 0, ack.Length);
}
Can you help me please.
Thank you in advance.

SisyB

Kurumi

7 years 5 months ago

Hi,

Changing the baud rate might be sometimes difficult. You did not tell the meter model.
One option is if you don't change the baud rate. Use 300. It's slower, but you can test with that.

I also find out that you are writing 050, not 051.

BR,

Mikko

SisyB

7 years 5 months ago

Hi Mikko,

I can actually change the baudate.I can set it to 300(0X30) or 9600(0x35) and i can see the difference on my data which proves that the baudrate has changed.
The issue is it does'nt take 051 .When i use 051 it would stream all data, but if i try to put onto programming mode using 051 i dont get any response from the meter.
And if i set to Manufacture specific mode (059) i get a response of 42 , which i cannot decipher its meaning.
The meter is As220 from Elster

Hi Mikko,

Using the manufacturer's software i can read the meter ,and can successfully switch to Programming MODE.
Send: 16:23:43,77 -- /?!<CR><LF>
Recv: 16:23:44,99 -- /ELS5\@V8.23 <CR><LF>
Send: 16:23:45,19 -- <ACK>051<CR><LF>
Recv: 16:23:45,72 -- <SOH>P0<STX>(********)<ETX>h Soll: h
Send: 16:23:45,93 -- <SOH>P1<STX>(********)<ETX>?
Recv: 16:23:46,16 -- <ACK>
Send: 16:23:46,37 -- <SOH>R5<STX>0.8.0()<ETX>_
Recv: 16:23:49,26 -- <STX>0.8.0()<ETX>: Soll: :
Send: 16:23:49,46 -- <SOH>B0<ETX>q