RuggedCom RuggedRouter RX1100 - Manual (Page 230)

25. Synchronous Serial Ports
Revision 1.14.3 230 RX1000/RX1100™
25. Synchronous Serial Ports
25.1. Introduction
This chapter familiarizes the user with configuring RuggedRouter to forward data from Synchronous
Serial ports over IP using the Raw Socket protocol. The RuggedRouter Serial Protocols Server (see
also
Configuring Serial Protocols ) that forwards data traffic from asynchronous serial ports over IP
networks can also be configured to run Raw Socket connections over synchronous serial ports.
25.1.1. Synchronous Serial Port Features
RuggedRouter Synchronous Serial ports provide the following features:
• up to four independent synchronous serial ports per RuggedRouter, two ports per slot
• configurable data rates from 2400 to 230400 bits per second
• internal or external clocking modes
• RTS/CTS hardware flow control
• HDLC framing
• support for the Raw Socket protocol - a means to transport data from a synchronous serial port
on the router to a specified remote IP address and TCP port
• up to eight TCP Raw Socket connections per port
• debugging facilities including connection tracing and statistics
25.1.2. Raw Socket Operation On Synchronous Ports
The Raw Socket protocol operates somewhat differently on synchronous ports from the way it does
on asynchronous ports. One important difference is that in the case of outgoing calls only, up to eight
TCP connections may be mapped to a single synchronous serial port. This means that data received
on the port will be transmitted to all configured TCP endpoints, and all data received from the TCP
endpoints will be transmitted on the synchronous port.
Another difference concerns framing. Forwarding to and from asynchronous serial ports involves
timeouts and "pack" characters in order to aid in framing, or packetization, for transmission on an IP
network. HDLC frames received on the synchronous port will be transmitted immediately on the TCP
connection, and incoming data on TCP connections are written directly to the port. Note, however,
that HDLC framing information is not preserved on transmission via TCP.
25.2. Synchronous Serial Port Configuration
The Synchronous Port Settings menu is accessed by clicking on Sync Serial in the Networking
folder of the main Webmin menu.