On Wed, 28 Jun 2017 10:55:47 -0700 (MST), turro75 <valerio.turr...@gmail.com> wrote:
>I don't know if useful, here You can find a terminal + serial to eth or >reversed based on lnet, custom serial component and richmemo > >https://github.com/Turro75/TCPLogger_V2.git ><https://github.com/Turro75/TCPLogger_V2.git> > Thanks, but I have two problems: 1) I have failed to install LNet into my Lazarus 1.6 on Windows. See thread titled "Installing LNet in Lazarus 1.6 fails" in the Lazarus list. So I turned to Indy instead, but I think LNet would serve me better. 2) I need the relay gateway to be running also on Raspberry Pi3, i.e. the system must be cross-platform and it seems like the example is for Windows (COM ports with strange syntax etc). 3) I also noted in the comments in TurSeriale.pas: "The Windows port driver does receive callbacks in chunks that are typically 8 bytes long. With ReceiveMode = rmRAW, TSeriale will simply pass this chunks on to the application without any processing." Does this mean that if a single character is received it is not passed along? My protocol is exchanging single bytes for state changes and these have rather tight timeouts as well, so a long delay in forwarding the bytes will break the protocol. State of my effort as of now: ============================= Server side: I am using ser2net on a RPi3 on the remote location to translate the serial port connection into a socket connection. This seems to work but there are issues. Client side: Here I have written a relaying application myself with Lazarus 1.6 and FPC 3.0.0. I used the FPC built-in serial unit as adviced in the hardware wiki for the serial port. For the TCP client I finally went with Indy's TIdTcpClient and it seemed to work a bit. Issues: For some unknown reason (so far) the remote side loses connection to the target system (no response after initially being able to talk to it). In fact this is reproducible 100%, the first handshake works and the system can be set to the new state, but on the next state change the 1-byte command is not responded to so the connection fails. In order to trace this I need to have better control at the remote side so I wanted to expand the Windows side client to be able to run in server mode so I can install it on the RPi3 instead of using ser2net. Then I think I could examine all data traffic with timing to figure out the problem. So my current aim is to convert the current program into an application that can run either as a server or a client on the network and do this: SERVER -------- - Listen for connection on a specific TCP port (only one allowed) - When client connects open the predefined serial port - Enter relay mode where all bytes coming in on the socket connection are sent to the serial port and all bytes coming in on the serial port are sent to teh socket. - Keep doing this until the TCP client disconnects, when the serial port is also closed and the system waits for another connect. - To not lock up forever, there should be a (long) timeout in the relay mode such that in the absence of incoming data the timeout is decremented until triggered. Then the ports are closed and the system goes to wait mode. CLIENT MODE ----------- - Wait for some connect command (not sure how to do this) - Connect to local serial port - Connect to remote TCP port - Enter relay mode as above if both connections succeed - Exit relay mode on some disconnect command - Disconnect both TCP and serial ports I would like to also add some data logging to this system so I can see what is happening on the lines. Using the FPC built-in serial unit I can handle the serial connection, but I have trouble with the TCP part since the Indy components are a bit too involved and hard to understand. So in order for the program to run as a server I need a TCP server component I can integrate into this without too much fussing about. There is only one single client allowed and data should not be processed at all, just transferred... (And I failed to install LNet in Lazarus...) -- Bo Berglund Developer in Sweden _______________________________________________ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
