Latest Documents:
The CAN232 ASCII manual includes all commands for setting up CAN232 though RS232 and send and receive CAN frames through RS232.
http://www.can232.com/?page_id=72
USBtin - Simple USB to CAN interface
USBtin is a simple to build USB to CAN interface. It can monitor CAN busses and transmit CAN messages. The common CAN baud rates are supported. USBtin implements the USB CDC class and creates a virtual comport on the host computer. The interface is controlled with simple commands over this serial port.