ethercat | Harmony 3 EtherCAT solutions

The function signature of your "clicked" callbacks is wrong. It should be of the form as described in the documentation:

I don't think it is possible to change the number of IO links while the program is executing. Whenever a change is made to some IO links, you have to reactivate the configuration.

Like you mentioned you can use conditional pragma's in combination with TcLinkTo attributes to change IO links.

I was able to get it working. After digging into the settings of the Dave project I copied the exact command line parameters for the GDB server from Dave into CLion and from then on the debugging worked as it should.

For security, the driver refuses to send these types of packets by default.

Of course, since you have the source code to the driver, you are free to modify this restriction however you like — it's your driver. You can add a line to specifically allow the 0x88A4 EtherType, or delete the entire if-statement to allow all EtherTypes. You can require the usermode process to be running as Administrator if it wants to send "suspicious" network frames.

A bit more detail on the security angle. If you allow untrusted users/programs to place arbitrary data onto the network, that may compromise or weaken network security. This is why the sample driver (and Windows in general) does not allow arbitrary programs to put arbitrary data on the network.

For example, a malicious program that has unrestricted access to the Ethernet layer can advertise a malicious DHCP server that points clients to a malicious DNS server, conduct ARP poisoning attacks on your switch, DoS a switch (with, for example, 802.3x PAUSE frames, or with LLDPDUs that undermine the QoS policy), or circumvent any firewall policies you might have.

These potential attacks aren't necessarily a deal-breaker: consider that this is roughly the equivalent of allowing someone to plug an arbitrary unmanaged device into an Ethernet jack on your network. If your network already has measures in place to defend against hostile Ethernet endpoints, then removing restrictions from the sample driver not making things much worse. Alternatively, if you have some level of trust for all the users & code on the PCs that will run your driver, then modifying the driver won't matter. Or if your threat model already assumes the network is hostile and unreliable, then removing these restrictions will only help fulfill your threat model's expectations. ;)

In order to enable this functionality all you need to do is Enable ADS Server on the EtherCAT device that you are trying to access.

There are a few setup steps that are required to make this work, but it is reasonably straight-forward.

1. Scan in IO from EtherCAT chain
2. Add a new 'Twincat Task with Image'
   • Added from the context menu of 'System>Tasks'
3. Create and link variable from added task to IO
   • Force the sync-unit updates and allow control of EtherCAT timing
   • I added a variable that linked to the SlaveCount with a UINT, very basic
4. For EtherCAT master enable 'Enable ADS Server' and 'Create Symbols'
5. Access Symbols as you would any other on the controller
   • Only oddity around this is that you need to access the CONTROLLER net ID, not the EtherCAT master, But you still use the port from the EtherCAT master

Where to find 'Enable ADS Server', 'Create Symbols' and ADS Port

Example Symbol path in the IO device list

The answer to your question is: "No, only in a multi-threaded context."

In a multi-threaded context almost anything you cannot imagine will happen. The background and context you provided is extensive but not sufficient to study this.

One thing Conv_shouldread = false; //If true, Conv_ReadAvail returns true apparently modifies (or determines) the outcome of if(ThreadSync.Conv_ReadAvail()) and it seem obvious that other threads are also interfering with this. I would, thus, clearly put the Conv_shouldread = false; inside the mutex protection.

But besides this, I must confess the problem could be clearly somewhere else and there can be a lot of side effects between different threads.

You will need two different tasks running at different speeds, determined by the baud rate of your communications and how often you want to process the data present on the buffer.

If you examine the example included in your reference link then you will see that then then there is two different tasks (2ms, 10ms cycle times). The high-speed task retrieves data directly from the serial port and loads it onto the message buffer, and the low-speed task processes the data.

Fixed problem by linking variable from PLC code to DevState-input of the device. Linking to plain InfoData doesn't seem to work though.