Q:  I am using the Komodo CAN Duo Interface and the Komodo GUI Software. What I want to do is loop CAN A to Can B. I connected CAN A+ to CAN B+,  CAN A- to CAN B-, and GND A to GND B. I need to send a CAN message from CAN A to CAN B and run some tests. If you can help me through this step by step, it would be greatly appreciated.

A: Thanks for your question!  The Komodo CAN Duo Interface features two independently customizable CAN channels that can simultaneously send CAN data and passively monitor CAN buses. To become familiar with the Komodo CAN Duo Interface and the Komodo GUI Software, you can start with sending messages between Channel A and Channel B on one Komodo interface using Komodo GUI. Here are the instructions you requested:

1. Connect the Komodo DB-9 CAN A port to the Komodo DB-9 CAN B port.
2. Connect the Komodo USB port to the  USB port of the computer.
3. Connect a 1K ohm resistor between CAN+ (pin 4) and CAN- (pin 2) in the Komodo block screw terminal CAN A port.
   Figure 1: Komodo Terminal Block
4. Open Komodo GUI – 1  on the computer. Select Analyzer → Connect → Select Komodo port A, and then click OK.
5. Open Komodo GUI – 2 on the computer. Select Analyzer → Connect → Select Komodo port B, and then click OK.
6. On Komodo GUI-1 click Mode → General CAN, and then configure as follows:

   1. Enable Active CAN Mode
   2. Bit rate: 125 KHz
   3. CAN ID: 0x123, DLC: 5
   4. Message: 1122 33 44 55
   5. Ch A
   6. Click Analyzer → Run

7. On Komodo GUI-2 click Mode → General CAN, and then configure as follows:

   1. Enable Active CAN Mode
   2. Bit rate: 125 KHz
   3. CAN ID: 0x456, DLC: 5
   4. Message: 66 77 88 99 00
   5. Ch B
   6. Click Analyzer → Run

8. On Komodo GUI-1, click "Send Message".
9. On Komodo GUI-2, click "Send Message".
10. Looking at the Komodo GUI Software, verity that both Komodo CAN Duo Interface ports receive the data correctly  as shown in the example below.

Figure 2: Results of Looping Channel A and Channel B

For more information about the Komodo Can Duo Interface, please see the following documents:

Komodo CAN Duo Interface

Getting Started - Komodo CAN Duo Interface

Komodo CAN Duo Interface Data Sheet

Komodo GUI Software

We hope this answers your question. If you have other questions about our Protocol Analyzers or other Total Phase products, feel free to email us at sales@totalphase.com or support@totalphase.com.