Microchip Technology MCP2515DM-PTPLS Data Sheet
2003-2012 Microchip Technology Inc.
DS21801G-page 27
MCP2515
REGISTER 4-1:
RXB0CTRL – RECEIVE BUFFER 0 CONTROL
(ADDRESS: 60h)
(ADDRESS: 60h)
U-0
R/W-0
R/W-0
U-0
R-0
R/W-0
R-0
R-0
—
RXM1
RXM0
—
RXRTR
BUKT
BUKT1
FILHIT0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
Unimplemented: Read as ‘0’
bit 6-5
RXM<1:0>: Receive Buffer Operating mode bits
11
= Turn mask/filters off; receive any message
10
= Receive only valid messages with extended identifiers that meet filter criteria
01
= Receive only valid messages with standard identifiers that meet filter criteria. Extended ID filter
registers RXFnEID8:RXFnEID0 are ignored for the messages with standard IDs.
00
= Receive all valid messages using either standard or extended identifiers that meet filter criteria.
Extended ID filter registers RXFnEID8:RXFnEID0 are applied to first two bytes of data in the
messages with standard IDs.
messages with standard IDs.
bit 4
Unimplemented: Read as ‘0’
bit 3
RXRTR: Received Remote Transfer Request bit
1
= Remote Transfer Request Received
0
= No Remote Transfer Request Received
bit 2
BUKT: Rollover Enable bit
1
= RXB0 message will rollover and be written to RXB1 if RXB0 is full
0
= Rollover disabled
bit 1
BUKT1: Read-only Copy of BUKT bit (used internally by the MCP2515)
bit 0
FILHIT0: Filter Hit bit – indicates which acceptance filter enabled reception of message
1
= Acceptance Filter 1 (RXF1)
0
= Acceptance Filter 0 (RXF0)
Note:
If a rollover from RXB0 to RXB1 occurs, the FILHIT bit will reflect the filter that accepted
the message that rolled over.
the message that rolled over.