Multipointtalk
MultiPoint Mode¶
This is a configuration in which more than two physically separate CAN buses are connected logically together via a Wi-Fi network.
See MultiPoint connections for information.
MultiPoint means that any CAN data:
- from the physical CAN bus of the Server is sent to each wirelessly connected peer, and
- from the CAN bus of any peer is sent to the Server.
It can be seen that data from the bus of one peer is not shared with other pairs.
No special configuration is required over and above that to establish a Bridge between two devices, as long as that device can connect.
In other words, when another CANlink® wireless 4000 device is added to the network, the Server will automatically send incoming CAN data to all peers. No additional configuration must be done to the Server.
Tip
When we talk about 'CAN bus' in a general sense, we refer to either of the two buses the CANlink® wireless 4000 supports.
Logically, they are treated in the same way, and very little distinction are made between them (apart from Node ID).
Therefore, when we discuss sending CAN data wirelessly, data from both buses will be sent wirelessly, and put onto the correct bus when received by the peer device.
Configuration
To establish more than one Client connection to a Wi-Fi Server, some configuration is required.
Typically, the first Client is connected with the following settings:
| Object | Server | 1st Client |
|---|---|---|
Access Point Mode0x3000:0x01 [Operating Mode] |
0x02 [Mini Access Point] |
0x01 [Infrastructure] |
WiFi SSID0x3000:0x02 |
as appropriate | as appropriate |
Authentication0x3000:0x04 [Authentication Type] |
0x07 [WPA/WPA2 Mixed] |
0x07 [WPA/WPA2 Mixed] |
Password0x3000:0x05 [WiFi Authentication Key](See Password Requirements) |
as appropriate | as appropriate |
Static IP Address0x3000:0x0A [WiFi IP Address] |
as appropriate | 🚫 |
DHCP0x3000:0x09 [DHCP Mode] |
0x02 [Server] |
0x01 [DHCP Client (WLAN infrastructure only)] |
RF channel0x3000:0x0F [WLAN - Access Point Channel] |
as appropriate | 🚫 |
| RF band. One of: - 0x3000:0x10 [Enable 2.4GHz WiFi Band / Infrastructure only]- 0x3000:0x11 [Enable 5GHz WiFi Band / Infrastructure only] |
🚫 | as appropriate |
IP Address0x3000:0x0A [IP Address] |
as appropriate | 🚫 |
Disable BT0x3008:0x03 [Bluetooth Enable] |
0x00 |
0x00 |
Disable BLE0x3008:0x02 [BLE Enable] |
0x00 |
0x00 |
Enable WiFi0x3008:0x02 [WiFi Enable] |
0x01 |
0x01 |
Server address0x3010:0x17 [EEP URL Address/WLAN Client only 1] |
🚫 | Value of 0x3000:0x0A [IP Address] in Server device |
Enable WiFi server0x3010:0x15 [EEP Connection Direction Configuration/Server or Client 1] |
0x02 [Server enabled] |
0x03 [Client enabled] |
Connection type0x3010:0x16 [EEP Connect Type 1] |
0x01 [TCP Socket] |
0x01 [TCP Socket] |
Socket Listen Port0x3010:0x18 [Socket Listen Port/WiFi only 1] |
(30000 by default) |
Value of 0x3010:0x18 [Socket Listen Port/WiFi only 1] in Server device |
There are different objects per Client connection. These have been highlighted in green.
By default each of the seven possible Client connections has a different default port:
| Connection | Object | Default Port |
|---|---|---|
| Client 1 | 0x3010:0x18 [Socket Listen Port/WiFi only 1] |
30 000 |
| Client 2 | 0x3011:0x18 [Socket Listen Port/WiFi only 2] |
30 001 |
| Client 3 | 0x3012:0x18 [Socket Listen Port/WiFi only 3] |
30 002 |
| Client 4 | 0x3013:0x18 [Socket Listen Port/WiFi only 4] |
30 003 |
| Client 5 | 0x3014:0x18 [Socket Listen Port/WiFi only 5] |
30 004 |
| Client 6 | 0x3015:0x18 [Socket Listen Port/WiFi only 6] |
30 005 |
| Client 7 | 0x3016:0x18 [Socket Listen Port/WiFi only 7] |
30 006 |
As we can see, the first Client connects by default to port 30000, which is the default port that the Server will open and listen on.
All Port numbers can be set to the same value. This is how this tutorial will continue.
The Server device must be configured for each Client connection.
Again, as can be seen, the settings for each Client are in a different object, from 0x3010 for Client one, through 0x3016 for Client seven.
Server Objects (0x3011 group) |
Server Value |
|---|---|
Enable WiFi server0x3011:0x15 [EEP Connection Direction Configuration/Server or Client 2] |
0x02 [Server enabled] |
Connection type0x3011:0x16 [EEP Connect Type 2] |
0x01 [TCP Socket] |
Socket Listen Port0x3011:0x18 [Socket Listen Port/WiFi only 1] |
30000 |
The second Client connection is configured exactly as in the prior table with the settings for the first Client.
After this Client device has been configured, three CANlink® wireless 4000 would be connected together:
For an additional Client connection, the values in the 0x3012 group. (And so forth):
Server Objects (0x3012 group) |
Value |
|---|---|
Enable WiFi server0x3012:0x15 [EEP Connection Direction Configuration/Server or Client 2] |
0x02 [Server enabled] |
Connection type0x3012:0x16 [EEP Connect Type 2] |
0x01 [TCP Socket] |
Socket Listen Port0x3012:0x18 [Socket Listen Port/WiFi only 1] |
30000 |
MultiTalk¶
This is a configuration in which more than two separate CAN buses are connected logically together, and all data is shared between all connected nodes. See MultiTalk connections for information.
The difference over MultiPoint is that incoming wireless data is also propagated to all other peers.
Since only one device (the Server) has more than one peer - only this device needs configuration.
When Wi-Fi connections have already been established, only one setting is required to enable MultiPoint.
| Step | Wi-Fi Server | Wi-Fi Client(s) |
|---|---|---|
Enable MultiTalk0x3008:0x04 [MultiTalk Enable] |
Set to 0x01 |
🚫 No configuration needed |