在G0的参考手册里有详细的如下描述:: Two voltage ranges are available: Range 1: High-performance range The main regulator provides a typical output voltage at 1.2V. The system clock frequency can be up to 64MHz. The Flash access time for read access is minimum, write and erase operations are possible. Range 2: Low-power range The main regulator provides a typical output voltage at 1.0V. The system clock frequency can be up to 16 MHz.The Flash memory access time for a read access is increased as compared to Range 1; write and erase operations are not possible.