UMAX141200. Wi-Fi to CAN Converter. Version 1
Page: 10-44
2.3.1 Communication Device
The
Communication Device
module
is responsible for the protocol conversion between CAN
and IP networks. It utilizes a proprietary communication protocol to communicate CAN
messages and other auxiliary information over the IP network.
The
Communication Device
supports a client/server communication model. In this model, the
converter has a primary server role, allowing external clients to establish independent
connections with the converter.
In addition to the server role, the converter can also act as a client, if the
Auto Connect to
Remote
configuration parameter is set to
Yes
. In this case, the converter will try to establish a
connection with a customer specified remote server.
The total number of remote connections is limited to 10. If the CAN network traffic is high, this
number should be further reduced, or the connections will become unstable due to limited
internal resources of the microcontroller, which are dynamically allocated between open
connections.
The
Communication Device
can use either UDP or TCP IP, depending on the value of the
Device Port Type
configuration parameter.
2.3.1.1 UDP Protocol
The UDP protocol is set by default. Since it is a connectionless protocol, one data socket
serves all device communication needs, see Figure 3.
New
connection?
Identify new connection
by analyzing incoming
traffic
No
Yes
Input/Output Communication
Up to 10
connections
Connection Maintenance
Server
Client
Server connection will
expire, if inactive
Client connection will
never expire
DeviceIpAddr:DevicePort
Device Communication Flow
Data Socket
Initialize remote connection if
AutoconnectToRemote==True
Figure 3. Communication Device. UDP Protocol
