Datasheet

© 2007 Microchip Technology Inc. DS21801E-page 29
MCP2515
REGISTER 4-3: BFPCTRL – RXnBF PIN CONTROL AND STATUS
(ADDRESS: 0Ch)
U-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
— — B1BFS B0BFS B1BFE B0BFE B1BFM B0BFM
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 Unimplemented: Read as ‘0’
bit 5 B1BFS: RX1BF
Pin State bit (Digital Output mode only)
- Reads as ‘0’ when RX1BF is configured as interrupt pin
bit 4 B0BFS: RX0BF Pin State bit (Digital Output mode only)
- Reads as ‘0’ when RX0BF is configured as interrupt pin
bit 3 B1BFE: RX1BF Pin Function Enable bit
1 = Pin function enabled, operation mode determined by B1BFM bit
0 = Pin function disabled, pin goes to high-impedance state
bit 2 B0BFE: RX0BF
Pin Function Enable bit
1 = Pin function enabled, operation mode determined by B0BFM bit
0 = Pin function disabled, pin goes to high-impedance state
bit 1 B1BFM: RX1BF Pin Operation Mode bit
1 = Pin is used as interrupt when valid message loaded into RXB1
0 = Digital Output mode
bit 0 B0BFM: RX0BF Pin Operation Mode bit
1 = Pin is used as interrupt when valid message loaded into RXB0
0 = Digital Output mode
REGISTER 4-4: RXBnSIDH – RECEIVE BUFFER n STANDARD IDENTIFIER HIGH
(ADDRESS: 61h, 71h)
R-x R-x R-x R-x R-x R-x R-x R-x
SID10 SID9 SID8 SID7 SID6 SID5 SID4 SID3
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 7-0 SID: Standard Identifier bits <10:3>
These bits contain the eight most significant bits of the Standard Identifier for the received message