arm数据定义伪指令（10） Chinese, example, 工作原理, 伪指令, 程序

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4.3.3 汇编语言程序示例以下是一个基于S3C4510B的串行通讯程序，关于S3C4510B的串行通讯的工作原理，可以参考第六章的相关内容，在此仅向读者说明一个完整汇编语言程序的基本结构：
********************************************************************************
Institute of Automation,Chinese Academy of Sciences
Description: This example shows the UART communication！
Author: JuGuang,Lee
Date:
********************************************************************************
UARTLCON0 EQU 0x3FFD000
UARTCONT0 EQU 0x3FFD004
UARTSTAT0 EQU 0x3FFD008
UTXBUF0 EQU 0x3FFD00C
UARTBRD0 EQU 0x3FFD014
AREA Init,CODE,READONLY
ENTRY
**************************************************
LED Display
**************************************************
LDR R1,=0x3FF5000
LDR R0,=&ff
STR R0,[R1]
LDR R1,=0x3FF5008
LDR R0,=&ff
STR R0,[R1]
*************************************************
UART0 line control register
*************************************************
LDR R1,=UARTLCON0
LDR R0,=0x03
STR R0,[R1]
**************************************************
UART0 control regiser
**************************************************
LDR R1,=UARTCONT0
LDR R0,=0x9
STR R0,[R1]
**************************************************
UART0 baud rate divisor regiser
Baudrate=19200，对应于50MHz的系统工作频率
***************************************************
LDR R1,=UARTBRD0
LDR R0,=0x500
STR R0,[R1]
***************************************************
Print the messages!
***************************************************
LOOP
LDR R0,=Line1
BL PrintLine
LDR R0,=Line2
BL PrintLine
LDR R0,=Line3
BL PrintLine
LDR R0,=Line4
BL PrintLine
LDR R1,=0x7FFFFF
LOOP1
SUBS R1,R1,#1
BNE LOOP1
B LOOP
***************************************************
Print line
***************************************************
PrintLine
MOV R4,LR
MOV R5,R0
Line
LDRB R1,[R5],#1
AND R0,R1,#&FF
TST R0,#&FF
MOVEQ PC,R4
BL PutByte
B Line
PutByte
LDR R3,=UARTSTAT0
LDR R2,[R3]
TST R2,#&40
BEQ PutByte
LDR R3,=UTXBUF0
STR R0,[R3]
MOV PC,LR
Line1 DCB &A,&D,"******************************************************************",0
Line2 DCB &A,&D,"Chinese Academy of Sciences,Institute of Automation,Complex System Lab.",0
Line3 DCB &A,&D," ARM Development Board Based on Samsung ARM S3C4510B.",0
Line4 DCB &A,&D,&A,&D,&A,&D,&A,&D,&A,&D,&A,&D,&A,&D,&A,&D,&A,&D,&A,&D,&A,&D,&A,&D,&A,&D,&A,&D,&A,&D,0
END