MSP430F2131如何进行时钟校准

关于DCO精度的问题，你一般需要考虑两个因素，一个是芯片的工作电压，一个是工作温度。

一般说DCO的精度，都会考虑在全温度范围，还是室温，工作电压时可变的，还是固定的某一个具体的电压值。

MSP430F2131的DCO的精度，可以参考datasheet的23页，里面很详细的说明了在室温下，全温下，不同工作电压下的温度。

https://www.ti.com.cn/cn/lit/ds/symlink/msp430f2131.pdf 

关于校准参数，我们提供了相关的程序

http://dev.ti.com/tirex/explore/node?node=AFBWDiHlS1d3fquUBkb3LQ__IOGqZri__LATEST 

//******************************************************************************
//  MSP430F21x2 Demo - DCO Calibration Constants Programmer
//
//  NOTE: THIS CODE REPLACES THE TI FACTORY-PROGRAMMED DCO CALIBRATION
//  CONSTANTS LOCATED IN INFOA WITH NEW VALUES. USE ONLY IF THE ORIGINAL
//  CONSTANTS ACCIDENTALLY GOT CORRUPTED OR ERASED.
//
//  Description: This code re-programs the F2xx DCO calibration constants.
//  A software FLL mechanism is used to set the DCO based on an external
//  32kHz reference clock. After each calibration, the values from the
//  clock system are read out and stored in a temporary variable. The final
//  frequency the DCO is set to is 1MHz, and this frequency is also used
//  during Flash programming of the constants. The program end is indicated
//  by the blinking LED.
//  ACLK = LFXT1/8 = 32768/8, MCLK = SMCLK = target DCO
//  //* External watch crystal installed on XIN XOUT is required for ACLK *//
//
//           MSP430F21x2
//         ---------------
//     /|\|            XIN|-
//      | |               | 32kHz
//      --|RST        XOUT|-
//        |               |
//        |           P1.0|--> LED
//        |           P2.1|--> SMLCK = target DCO
//
//  A. Dannenberg
//  Texas Instruments Inc.
//  December 2007
//  Built with CCE Version: 3.2.0 and IAR Embedded Workbench Version: 3.41A
//******************************************************************************

另外我们提供了

https://www.ti.com/lit/an/slaa336a/slaa336a.pdf