Simplest CAN Controller Ever Made for HDL Design—Reference Designs or Documentation?

Hello everyone,
I am working on creating a CAN IP, for that I need to understand how a CAN controller and a CAN Transceiver work.
There is a variety of CAN controllers, But I am looking for the simplest one, because I will have to do design of the controller by myself, using a Hardware Description Language.
I wonder if there are documents which explain functionalities of each small block in more details than the Datasheets.

Thanks in advance.

Yasmine, I have very little knowledge of CAN, but there are some good tutorials on the net.  Google CAN bus tutorial and you will get a good selection.  There is a good one by National Semiconductor as a PDF, and a video course in several parts by Kvaser.  I hope these might help you.

A full CAN 2.0 implementation with message filtering is supplied by the MCP2510 14-pin standalone CAN controller. Therefore, the host microcontroller is relieved from performing any CAN-bus-related overhead. This is a key feature given the limited available code space of the PIC12C672. The PCA-82C251 transceiver was selected arbitrarily because this article focuses on implementing the CAN protocol, and the physical layer is undefined by CAN.The PIC12C672 uses all six available I/O pins. It also takes advantage of the internal RC oscillator, which provides a 4-MHz system clock that translates into a 1-µs instruction cycle. Two I/O ports are used for analog input, while four I/Os are used to interface to the MCP2510 (three SPI and one interrupt).An 8-MHz crystal is used to operate the MCP2510. While the three TXnRTS pins are configured as general-purpose inputs, the RXnBF pins are configured as general-purpose outputs. As a result, all of the pins the MCU lost for the SPI interface are regained. The TXnRTS inputs are connected to switches. These pins have internal pull-up resistors that cause the input to read as a logic "1" when the switch is open. The RXnBF outputs are connected to LEDs.