The 82527 serial communications controller is a highly integrated device that performs serial communication according to the CAN protocol It performs all serial communication functions such as transmission and reception of messages message filtering transmit search and interrupt search with minimal interaction from the host microcontroller or CPU The 82527 is Intel's first device to support the standard and extended message frames in CAN Specification 2 0 Part B It has the capability to transmit receive and perform message filtering on extended message frames Due to the backwardly compatible nature of CAN Specification 2 0 the 82527 also fully supports the standard message frames in CAN Specification 2 0 Part A The 82527 features a powerful CPU interface that offers flexibility to directly interface to many different CPUs It can be configured to interface with CPUs using an 8-bit multiplexed 16-bit multiplexed or 8-bit non-multiplexed address data bus for Intel and non-Intel architectures A flexible serial interface (SPI) is also available when a parallel CPU interface is not required The 82527 provides storage for 15 message objects of 8-byte data length Each message object can be configured as either transmit or receive except for the last message object The last message object is a receive-only buffer with a special mask design to allow select groups of different message identifiers to be received