38.7.33 Rx Buffer / FIFO Element Size Configuration

This register is write-restricted and only writable if bit fields CCCR.CCE bit (CCCR <1>) = 1 and CCCR.INIT bit (CCCR <0>) = 1.

Configures the number of data bytes belonging to an Rx Buffer / Rx FIFO element. Data field sizes >8 bytes are intended for CAN FD operation only.

Table 38-50. Register Bit Attribute Legend
Symbol	Description	Symbol	Description	Symbol	Description
R	Readable bit	HC	Cleared by Hardware	(Grey cell)	Unimplemented
W	Writable bit	HS	Set by Hardware	X	Bit is unknown at Reset
K	Write to clear	S	Software settable bit	—	—

Name:	RXESC
Offset:	0xBC
Reset:	0x00000000
Property:	Write-restricted


Bit	31	30	29	28	27	26	25	24

Access
Reset


Bit	23	22	21	20	19	18	17	16

Access
Reset


Bit	15	14	13	12	11	10	9	8
						RBDS[2:0]
Access						R/W	R/W	R/W
Reset						0	0	0


Bit	7	6	5	4	3	2	1	0
		F1DS[2:0]				F0DS[2:0]
Access		R/W	R/W	R/W		R/W	R/W	R/W
Reset		0	0	0		0	0	0

Bits 10:8 – RBDS[2:0] Rx Buffer Data Field Size

In case the data field size of an accepted CAN frame exceeds the data field size configured for the matching Rx Buffer, only the number of bytes as configured by RXESC are stored to the Rx Buffer element. The rest of the frame’s data field is ignored.

Value	Name	Description
0x0	DATA8	8 byte data field.
0x1	DATA12	12 byte data field.
0x2	DATA16	16 byte data field.
0x3	DATA20	20 byte data field.
0x4	DATA24	24 byte data field.
0x5	DATA32	32 byte data field.
0x6	DATA48	48 byte data field.
0x7	DATA64	64 byte data field.

Bits 6:4 – F1DS[2:0] Rx FIFO 1 Data Field Size

In case the data field size of an accepted CAN frame exceeds the data field size configured for the matching Rx FIFO 1, only the number of bytes as configured by RXESC are stored to the Rx FIFO 1 element. The rest of the frame’s data field is ignored.

Value	Name	Description
0x0	DATA8	8 byte data field.
0x1	DATA12	12 byte data field.
0x2	DATA16	16 byte data field.
0x3	DATA20	20 byte data field.
0x4	DATA24	24 byte data field.
0x5	DATA32	32 byte data field.
0x6	DATA48	48 byte data field.
0x7	DATA64	64 byte data field.

Bits 2:0 – F0DS[2:0] Rx FIFO 0 Data Field Size

In case the data field size of an accepted CAN frame exceeds the data field size configured for the matching Rx FIFO 0, only the number of bytes as configured by RXESC are stored to the Rx FIFO 0 element. The rest of the frame’s data field is ignored.

Value	Name	Description
0x0	DATA8	8 byte data field.
0x1	DATA12	12 byte data field.
0x2	DATA16	16 byte data field.
0x3	DATA20	20 byte data field.
0x4	DATA24	24 byte data field.
0x5	DATA32	32 byte data field.
0x6	DATA48	48 byte data field.
0x7	DATA64	64 byte data field.