Data Sheet

© 2005 Microchip Technology Inc. Preliminary DS21801D-page 31
MCP2515
REGISTER 4-7: RXBnEID0 – RECEIVE BUFFER n EXTENDED IDENTIFIER LOW
(ADDRESS: 64h, 74h)
REGISTER 4-8: RXBnDLC – RECEIVE BUFFER n DATA LENGHT CODE
(ADDRESS: 65h, 75h)
REGISTER 4-9: RXBnDM – RECEIVE BUFFER n DATA BYTE M
(ADDRESS: 66h - 6Dh, 76h - 7Dh)
R-x R-x R-x R-x R-x R-x R-x R-x
EID7 EID6 EID5 EID4 EID3 EID2 EID1 EID0
bit 7 bit 0
bit 7-0 EID: Extended Identifier bits <7:0>
These bits hold the least significant eight bits of the Extended Identifier for the received
message
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
U-0 R-x R-x R-x R-x R-x R-x R-x
— RTR RB1 RB0 DLC3 DLC2 DLC1 DLC0
bit 7 bit 0
bit 7 Unimplemented: Reads as ‘0’
bit 6 RTR: Extended Frame Remote Transmission Request bit
(valid only when RXBnSIDL.IDE = ‘1’)
1 = Extended Frame Remote Transmit Request Received
0 = Extended Data Frame Received
bit 5 RB1: Reserved Bit 1
bit 4 RB0: Reserved Bit 0
bit 3-0 DLC: Data Length Code bits <3:0>
Indicates number of data bytes that were received
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
R-x R-x R-x R-x R-x R-x R-x R-x
RBnDm7 RBnDm6 RBnDm5 RBnDm4 RBnDm3 RBnDm2 RBnDm1 RBnDm0
bit 7 bit 0
bit 7-0 RBnDm7:RBnDm0: Receive Buffer n Data Field Bytes m
Eight bytes containing the data bytes for the received message
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