I have a Komodo Duo CAN Interface that I am using to read CAN messages from two ESR (electronically scanning radar) units. I have successfully connected to the Komodo device with a reading process.

Figure 1: Komodo CAN Duo Interface

I need to use a different process for sending messages to the Komodo interface. As the timing for sending messages is independent of reading messages, I expect separate processes to work best. However, when I try to connect with a second process, I get the "Unable to connect" error. This does not seem correct; I should be able to connect to a USB device with more than one process. I am using the Linux API on a Slackware 12.0 Linux distribution on a 2.6 kernel. Can you help me make this work?

Thanks for your question! It looks like your application requires the multi-threaded use of the Komodo interface functionality for a single port.  Each port of the Komodo CAN Duo Interface is independent - they can be used simultaneously in different threads. This functionality is supported with the Komodo API software. Each Komodo API call can be wrapped with a thread-safe locking mechanism before and after invoking the command.

For details about threading and asynchronous messages, please refer to the Applications Notes section of the Komodo CAN Interface User Manual. Details about Komodo API software are provided in the section API Documentation. Our API Software supports many operating systems, including Linux. Examples are provided with the API software, which you can use as is or to customize for your specific setups.

Additional resources that you may find helpful include the following:

• Komodo CAN Interface User Manual
• Komodo API Documentation

We hope this answers your questions. If you have other questions about our CAN interfaces or other Total Phase products, feel free to email us at sales@totalphase.com, or if you already own one of our devices and have a technical question, please submit a request for technical support.