NXP Semiconductors LPC24XX UM10237 - Manual (Page 467)

UM10237_4 © NXP B.V. 2009. All rights reserved.
User manual Rev. 04 — 26 August 2009 467 of 792
1. How to read this chapter
The CAN controller in available on parts LPC2458 and LPC2460/68/70/78.
2. Basic configuration
The CAN1/2 peripherals are configured using the following registers:
1. Power: In the PCONP register ( Table 4–63 ), set bits PCAN1/2.
Remark: On reset, the CAN1/2 blocks are disabled (PCAN1/2 = 0).
2. Peripheral clock: In the PCLK_SEL0 register ( Table 4–56 ), select PCLK_CAN1/2 and,
for the acceptance filter, PCLK_ACF. PCLK_CAN1/2 and PCLK_ACF must be set to
the same value.
Remark: If CAN baudrates above 100 kbit/s (see Table 18–425 ) are needed, do not
select the IRC as the clock source (see Table 4–42 ).
3. Wakeup: Use the INTWAKE register ( Table 4–62 ) to enable the CAN controllers to
wake up the microcontroller from Power-down mode.
4. Pins: Select CAN1/2 pins and pin modes in registers PINSELn and PINMODEn (see
Section 9–5 ).
5. Interrupts: CAN interrupts are enabled using the CAN1/2IER registers
( Table 18–424 ). Interrupts are enabled in the VIC using the VICIntEnable register
( Table 7–106 ).
6. CAN controller initialization: see CANMOD register ( Section 18–8.1 ).
3. CAN controllers
Controller Area Network (CAN) is the definition of a high performance communication
protocol for serial data communication. The CAN Controller is designed to provide a full
implementation of the CAN-Protocol according to the CAN Specification Version 2.0B.
Microcontrollers with this on-chip CAN controller are used to build powerful local networks
by supporting distributed real-time control with a very high level of security. The
applications are automotive, industrial environments, and high speed networks as well as
low cost multiplex wiring. The result is a strongly reduced wiring harness and enhanced
diagnostic and supervisory capabilities.
The CAN block is intended to support multiple CAN buses simultaneously, allowing the
device to be used as a gateway, switch, or router among a number of CAN buses in
various applications.
The CAN module consists of two elements: the controller and the Acceptance Filter. All
registers and the RAM are accessed as 32 bit words.
UM10237
Chapter 18: LPC24XX CAN controllers CAN1/2
Rev. 04 — 26 August 2009 User manual