Data Sheet
Table Of Contents
- 1.0 Device Overview
- 2.0 Can Message Frames
- 3.0 Message Transmission
- 4.0 Message Reception
- 5.0 Bit Timing
- 6.0 Error Detection
- 7.0 Interrupts
- 8.0 Oscillator
- 9.0 RESET
- 10.0 Modes of Operation
- 11.0 Register Map
- 12.0 SPI™ Interface
- 12.1 Overview
- 12.2 Reset Instruction
- 12.3 Read Instruction
- 12.4 Read RX Buffer Instruction
- 12.5 Write Instruction
- 12.6 Load TX Buffer Instruction
- 12.7 Request-To-Send (RTS) Instruction
- 12.8 Read Status Instruction
- 12.9 RX Status Instruction
- 12.10 Bit Modify Instruction
- Figure 12-1: Bit Modify
- Table 12-1: SPI™ Instruction Set
- Figure 12-2: Read instruction
- Figure 12-3: Read RX Buffer Instruction
- Figure 12-4: Byte Write instruction
- Figure 12-5: Load TX Buffer
- Figure 12-6: Request-to-send (RTS) instruction
- Figure 12-7: BIT Modify instruction
- Figure 12-8: Read Status instruction
- Figure 12-9: RX StatUs Instruction
- Figure 12-10: SPI™ Input Timing
- Figure 12-11: SPI™ Output TIming
- 13.0 Electrical Characteristics
- 14.0 PackAging Information

MCP2515
DS21801D-page 42 Preliminary © 2005 Microchip Technology Inc.
REGISTER 5-1: CNF1 – CONFIGURATION 1 (ADDRESS: 2Ah)
REGISTER 5-2: CNF2 – CONFIGURATION 1 (ADDRESS: 29h)
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
SJW1 SJW0 BRP5 BRP4 BRP3 BRP2 BRP1 BRP0
bit 7 bit 0
bit 7-6 SJW: Synchronization Jump Width Length bits <1:0>
11 = Length = 4 x T
Q
10 = Length = 3 x TQ
01 = Length = 2 x TQ
00 = Length = 1 x TQ
bit 5-0 BRP: Baud Rate Prescaler bits <5:0>
TQ = 2 x (BRP + 1)/FOSC
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/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
BTLMODE SAM PHSEG12 PHSEG11 PHSEG10 PRSEG2 PRSEG1 PRSEG0
bit 7 bit 0
bit 7 BTLMODE: PS2 Bit Time Length bit
1 = Length of PS2 determined by PHSEG22:PHSEG20 bits of CNF3
0 = Length of PS2 is the greater of PS1 and IPT (2 T
Q)
bit 6 SAM: Sample Point Configuration bit
1 = Bus line is sampled three times at the sample point
0 = Bus line is sampled once at the sample point
bit 5-3 PHSEG1: PS1 Length bits<2:0>
(PHSEG1 + 1) x T
Q
bit 2-0 PRSEG: Propagation Segment Length bits <2:0>
(PRSEG + 1) x TQ
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