STM32 采用DMA的方式实现ADC功能-This example describes how to use the ADC1 and DMA to transfer continuously

converted data　ADC1 to memory.

The ADC1 is configured to convert continuously channel14.

Each time an end of conversion occurs the DMA transfers, in circular mode, the

converted data　ADC1 DR register to the ADCConvertedValue variable.

The ADC1 clock is set to 12 MHz on Value line devices and to 14MHz on other

devices.