Modular Can Cores - STMicroelectronics SPC572L series Reference Manual

CAN Subsystem
44.3

Modular CAN cores

CAN functionality conforms to CAN specification V2.0B active for each CAN node.The
M_CAN performs communication according to the CAN protocol specification 2.0 part A,B
and to CAN FD 1.0.Flexible assignment of Message Objects to nodes.
The bit rate can be programmed to values up to 1 Mbit/s. Additional transceiver hardware is
required for connection to the physical layer.
The message storage is intended to be a single-ported Message RAM outside of the
module. It is connected to the M_CAN via the Generic Master Interface. Depending on the
chosen device, multiple M_CAN controllers can share the same Message RAM.
All functions concerning the handling of messages are implemented by the Rx Handler and
the Tx Handler. The Rx Handler manages message acceptance filtering, the transfer of
received messages from the CAN core to the Message RAM as well as providing receive
message status information. The Tx Handler is responsible for the transfer of transmit
messages from the Message RAM to the CAN core as well as providing transmit status
information.
Acceptance filtering is implemented by a combination of up to 128 filter elements where
each one can be configured as a range, as a bit mask, or as a dedicated ID filter.
The M_CAN's clock domain concept allows the separation between the high precision CAN
clock and the Host clock, which may be generated by an FMPLL.
998/2058 DocID027809 Rev 4
RM0400