NXP Semiconductors UM10237 8.6 Bus Timing Register (CAN1BTR - 0xE004 4014, CAN2BTR - 0xE004 8014)

UM10237_2 © NXP B.V. 2008. All rights reserved.
User manual Rev. 02 — 19 December 2008 485 o f 792
NXP Semiconductors UM10237
Chapter 18: LPC24XX CAN controllers CAN1/2
8.6 Bus Timing Register (CAN1BTR - 0xE004 4014, CAN2BTR -
0xE004 8014)
This register controls how various CAN timings are derived from the APB clock. It defines
the values of the Baud Rate Prescaler (BRP) and the Synchronization Jump Width (SJW).
Furthermore, it defines the length of the bit period, the location of the sample point and the
number of samples to be taken at each sample point. It can be read at any time but can
only be written if the RM bit in CANmod is 1.
Table 424. Interrupt Enable Register (CAN1IER - address 0xE004 4010, CAN2IER - address
0xE004 8010) bit description
Bit Symbol Function Reset
Value RM Set
0 RIE Receiver Interrupt Enable. When the Receive Buffer Status is 'full',
the CAN Controller requests the respective interrupt. 0X
1 TIE1 Transmit Interrupt Enable for Buffer1. When a message has been
successfully transmitted out of TXB1 or Transmit Buffer 1 is
accessible again (e.g. after an Abort Transmission command), the
CAN Controller requests the respective interrupt.
0X
2 EIE Error Warning Interrupt Enable. If the Error or Bu s Status change
(see Status Register), the CAN Controller requests the respective
interrupt.
0X
3 DOIE Data Overrun Interrupt Enable. If the Data Overrun Status bit is
set (see Status Register), the CAN Controller requests the
respective interrupt.
0X
4 WUIE Wake-Up Interrupt Enable. If the sleeping CAN controller wakes
up, the respective interrupt is requested. 0X
5 EPIE Error Passive Interrupt Enable. If the error status of t he CAN
Controller changes from error active to error passive or vice versa,
the respective interrupt is requested.
0X
6 ALIE Arbitration Lost Interrupt Enable. If the CAN Controller has lost
arbitration, the respective interrupt is requested. 0X
7 BEIE Bus Error Interrupt Enable. If a bus error has been detected, the
CAN Controller requests the respective interrupt. 0X
8 IDIE ID Ready Interrupt Enable. When a CAN identifier has been
received, the CAN Controller requests the respective interrupt. 0X
9 TIE2 Transmit Interrupt Enable for Buffer2. When a message has been
successfully transmitted out of TXB2 or Transmit Buffer 2 is
accessible again (e.g. after an Abort Transmission command), the
CAN Controller requests the respective interrupt.
0X
10 TIE3 Transmit Interrupt Enable for Buffer3. When a message has been
successfully transmitted out of TXB3 or Transmit Buffer 3 is
accessible again (e.g. after an Abort Transmission command), the
CAN Controller requests the respective interrupt.
0X
31:11 - Reserved, user software should not write ones to reserved bits.
The value read from a reserved bit is not defined. NA