Freescale Semiconductor MCF5480 - Manual (Page 575)

External Signals
MCF548x Reference Manual, Rev. 3
Freescale Semiconductor 21-5
21.2 External Signals
The FlexCAN module has two I/O signals connected to the external MPU pins: CANTX and CANRX.
Note that the general purpose I/O (GPIO) must be configured to enable the peripheral function of the
appropriate pins (refer to Chapter 15, “GPIO” ) prior to configuring a FlexCAN channel.
21.2.1 CANTX[1:0]
CANTXn transmits serial data to the CAN bus transceiver.
21.2.2 CANRX[1:0]
CANRXn receives serial data from the CAN bus transceiver.
21.3 Memory Map/Register Definition
21.3.1 FlexCAN Memory Map
The FlexCAN module address space is split into 128 bytes starting at the base address, and then an extra
256 bytes starting at the base address +128. The upper 256 are fully used for the message buffer structures,
as described in Section 21.4.2, “Message Buffer Memory Map .” Out of the lower 128 bytes, only part is
occupied by various registers.
Table 21-1. FlexCAN Memory Map
MBAR Offset
Name Byte0 Byte1 Byte2 Byte3 Access
FlexCAN0 FlexCAN1
0xA000 0xA800 FlexCAN module
configuration register
CANMCR S
0xA004 0xA804 FlexCAN control register CANCTRL S/U
0xA008 0xA808 Timer register TIMER S/U
0xA00C 0xA80C Reserved —
0xA010 0xA8010 Rx global mask RXGMASK S/U
0xA014 0xA814 Rx buffer 14 mask RX14MASK S/U
0xA018 0xA818 Rx buffer 15 mask RX15MASK S/U
0xA01C 0xA81C Error counter register ERRCNT S/U
0xA020 0xA820 Error and status register ERRSTAT S/U
0xA024 0xA824 Reserved —
0xA028 0xA828 Interrupt mask register Reserved IMASK S/U
0xA02C 0xA82C Reserved —
0xA030 0xA830 Interrupt flag register Reserved IFLAG S/U