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I have a CAN bus network that I want to test. I want to send CAN messages over my computer and see the responses. I have a Microchip kit with CAN that sends the responses over USB Mini and can be read by their application. I don't know in what format they come.

I also have an OBD II-to-USB converter with the ELM327 chip.

Which bus terminal/monitor can I use?

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    \$\begingroup\$ Is this in an auto environment or using can for general purpose bus? \$\endgroup\$ – Kellenjb Jul 7 '11 at 22:24
  • \$\begingroup\$ I don't know what you mean by auto environment but I want to integrate a CAN node on a car CAN network and I need to get the oil temperature but I'm not sure how (the messages are really complicated to understand) \$\endgroup\$ – rnunes Jul 7 '11 at 22:43
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    \$\begingroup\$ canbus can be used in other environments. What you are looking for specifically is how to interface with obd-ii. \$\endgroup\$ – Kellenjb Jul 7 '11 at 22:57
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It appears that your question is not about CAN or even OBD2, but whatever protocol the ELM327 chip presents over the USB. If I understand it right (and I very well may not), the ELM chip tries to make the OBD information more uniform despite differences between manufacturers. If so, they surely must document how to talk to their chip. Did you look around for the protocol.

It also seems like you have access to the raw CAN bus via the Microchip converter. In that case you need to know the OBD2 standard, and perhaps how your particular car handles some of the proprietary aspects. The official OBD2 standard may be expensive, but I expect there is a lot about it on the net anyway.

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  • \$\begingroup\$ My big problem is: I want to send frames to a CAN network over my computer and see the response. The hardware that I have it's just know if it's enough for that, if you have any suggestions on new hardware or software it will be appreciated. \$\endgroup\$ – rnunes Jul 8 '11 at 10:55
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I've used the Microchip CAN bus analyzer tool to send and receive data over a proprietary CAN bus network. I'm not sure if the device is compatible with OBD2, but it seems like if you knew the format of the packets you could use this device to send/receive OBD2 packets.

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  • \$\begingroup\$ I STRONGLY recommend against getting this tool. I have it and have been very disappointed. No drivers for x64 even though I have had a support ticket for over a year. No API available. The software is difficult to use and doesn't handle extended identifiers properly. When running the CAN bus at 1mbps it was dropping more than half of the messages. \$\endgroup\$ – Erik Jul 8 '11 at 22:29
  • \$\begingroup\$ mjh2007: I am not downvoting your answer because it is not your fault I found the tool lacking. \$\endgroup\$ – Erik Jul 8 '11 at 22:30
  • \$\begingroup\$ I admit I’ve had problems with the Microchip CAN bus analyzer as well. It works best on low speed networks with very little CAN bus traffic. \$\endgroup\$ – mjh2007 Jul 27 '11 at 17:22
  • \$\begingroup\$ UPDATE: Microchip released v2.0 of the CAN Bus Analyzer software 11/3/2011. I just started using it, but so far it seems much better than the previous version. \$\endgroup\$ – mjh2007 Dec 7 '11 at 18:47
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I have used and continue to use the PEAK PCAN-USB. It's cheap, robust, and PEAK also provide you with API libraries so you can write your own programs for it. Or you can use the supplied PCAN-View program to read and write to the bus. As you mention automotive, you can also get a fault-tolerant adapter for it too.

PCAN USB

PCAN-TJA1054

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  • \$\begingroup\$ I've the same problem. i know that is not an answer but i don't know how post to BullBoyShoes this question. I've a peak usb-can cable and a peak obd-can cable that i had connected to a obd but with a peak view don't see nothing. can you give me a clarification about how you take obdinfo...thanks a lot please say me how contact this user without open a new topic. sorry again. \$\endgroup\$ – user1846891 May 15 '13 at 9:58

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