/** ***************************************************************************** @example ADC1_DMA.c @brief This example shows how to initialize the ADC1 for DMA operation - It implements the RTD demo similar to RTD_DEMO project except it uses DMA operation - This also sets up the SINC2 filter DMA output to measure across the RTD - ADC1 is used to measure an RTD input connected across AIN0 and AIN1. - AIN6 is used as the excitation current source for the RTD - REFIN+/REFIN- are the ADC external reference inputs - 100ohm PT100 RTD expected connected to AIN0 and AIN1 - To eliminate drift elements the following is the measurement sequence: - 1) Measure AIN1/AGND v Internal 1.2V reference to derive exact Excitation current value - 2) Measure AIN0/AGND as a diagnostic - should equal sum of steps 1 and 2. - 3) Measure AIN0/AIN1 v Internal Vref to determine voltage across RTD (vRTD) - 4) RRTD is determined and final RTD temeprature calculated. - The RTD reading is linearized and sent to the UART in a string format. - Default Baud rate is 9600 - EVAL-ADuCM360MKZ or similar hardware is assumed - Results will be more accurate if System calibration is added. @version V0.2 @author ADI @date February 2013 @par Revision History: - V0.1, October 2012: initial version. - V0.2, February 2013: Fixed a bug in SendString(). All files for ADuCM360/361 provided by ADI, including this file, are provided as is without warranty of any kind, either expressed or implied. The user assumes any and all risk from the use of this code. It is the responsibility of the person integrating this code into an application to ensure that the resulting application performs as required and is safe. **/解释上述代码注释的意思