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?
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.
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.
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.
