MSP430具有哪几种低功耗模式？

MSP430除了active模式外，还有低功耗模式（Low-power mode）即LPM0、LPM1、LPM2、LPM3、LPM4，由状态寄存器中的CPUOFF、OSCOFF、SCG0、SCG1比特位设置。



官方手册中的六种低功耗模式对应的时钟状态如下：
The following six operating modes can be configured by software:
Active mode (AM)


All clocks are active
Low-power mode 0(LPM0)
CPU is disabled
ACLK and SMCLK remain active,
MCLK is disabled
Low-power mode 1(LPM1)
CPU is disabled
ACLK and SMCLK remain active
MCLK is disabled
DCO’s dc generator is disabled if DCO not used in active mode
Low-power mode 2 (LPM2)
CPU is disabled
MCLK and SMCLK are disabled
DCO’s dc generator remains enabled
ACLK remains active
Low-power mode 3(LPM3)
CPU is disabled
MCLK and SMCLK are disabled
DCO’s dc generator is disabled
ACLK remains active
Low-power mode 4(LPM4)
CPU is disabled
ACLK is disabled
MCLK and SMCLK are disabled
DCO’s dc generator is disabled
Crystal oscillator is stopped
当VCC为3.0V时 LPM4消耗最低 因为此时关闭所有内部时钟信号，此时只能用外部中断唤醒


官方头文件所给出的实现语句：
#define LPM0      __bis_SR_register(LPM0_bits)     /* Enter Low Power Mode 0 */
#define LPM0_EXIT __bic_SR_register_on_exit(LPM0_bits) /* Exit Low Power Mode 0 */
#define LPM1      __bis_SR_register(LPM1_bits)     /* Enter Low Power Mode 1 */
#define LPM1_EXIT __bic_SR_register_on_exit(LPM1_bits) /* Exit Low Power Mode 1 */
#define LPM2      __bis_SR_register(LPM2_bits)     /* Enter Low Power Mode 2 */
#define LPM2_EXIT __bic_SR_register_on_exit(LPM2_bits) /* Exit Low Power Mode 2 */
#define LPM3      __bis_SR_register(LPM3_bits)     /* Enter Low Power Mode 3 */
#define LPM3_EXIT __bic_SR_register_on_exit(LPM3_bits) /* Exit Low Power Mode 3 */
#define LPM4      __bis_SR_register(LPM4_bits)     /* Enter Low Power Mode 4 */
#define LPM4_EXIT __bic_SR_register_on_exit(LPM4_bits) /* Exit Low Power Mode 4 */


将以上语句移植至Energia