MSP430 串口通信 程序

;******************************************************************************
;   MSP-FET430P140 Demo - USART0, Ultra-Low Pwr UART 9600 RX/TX, 32kHz ACLK
;
;   Description: This program demonstrates a full-duplex 9600-baud UART using
;   USART0 and a 32kHz crystal.  The program will wait in LPM3, and receive
;   a string1 into RAM starting at 200h, and echo back the complete string.
;   ACLK = LFXT1 = UCLK0, MCLK = SMCLK = default DCO ~ 800KHz
;   Baud rate divider with 32768hz XTAL @9600 = 32768Hz/9600 = 3.41 (0003h 4Ah )
;   //* An external watch crystal is required on XIN XOUT for ACLK *//
;
;                MSP430F149
;             -----------------
;         /|\|              XIN|-
;          | |                 | 32kHz
;          --|RST          XOUT|-
;            |                 |
;            |             P3.4|----------->
;            |                 | 9600 - 8N1
;            |             P3.5|<-----------
;
;   CPU registers used
#define     PointerTX  R4
#define     PointerRX  R5
;
String1     EQU     0200h
;
;   M. Buccini
;   Texas Instruments Inc.
;   Feb 2005
;   Built with IAR Embedded Workbench Version: 3.21A