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文字池答案是否正确<br />UARTLCON0 EQU 0x3FFD000<br />UARTCONT0 EQU 0x3FFD004<br />UARTSTAT0 EQU 0x3FFD008<br />UTXBUF0 EQU 0x3FFD00C<br />UARTBRD0 EQU 0x3FFD014<br />AREA Init,CODE,READONLY<br />ENTRY<br />;**************************************************<br />;LED Display<br />;**************************************************<br />LDR R1,=0x3FF5000<br />LDR R0,=&ff<br />STR R0,[R1]<br />LDR R1,=0x3FF5008<br />LDR R0,=&ff<br />STR R0,[R1]<br />;*************************************************<br />;UART0 line control register<br />;*************************************************<br />LDR R1,=UARTLCON0<br />LDR R0,=0x03<br />STR R0,[R1]<br />;**************************************************<br />;UART0 control regiser<br />;**************************************************<br />LDR R1,=UARTCONT0<br />LDR R0,=0x9<br />STR R0,[R1]<br />;**************************************************<br />;UART0 baud rate divisor regiser<br />;Baudrate=19200，对应于50MHz 的系统工作频率<br />;***************************************************<br />LDR R1,=UARTBRD0<br />LDR R0,=0x500<br />STR R0,[R1]<br />;***************************************************<br />;Print the messages!<br />;***************************************************<br />LOOP<br />LDR R0,=Line1<br />BL PrintLine<br />LDR R0,=Line2<br />BL PrintLine<br />LDR R0,=Line3<br />BL PrintLine<br />LDR R0,=Line4<br />BL PrintLine<br />LDR R1,=0x7FFFFF<br />LOOP1<br />SUBS R1,R1,#1<br />BNE LOOP1<br />B LOOP<br />;***************************************************<br />;Print line<br />;***************************************************<br />PrintLine<br />MOV R4,LR<br />MOV R5,R0<br />Line<br />LDRB R1,[R5],#1<br />AND R0,R1,#&FF<br />TST R0,#&FF<br />MOVEQ PC,R4<br />BL PutByte<br />B Line<br />PutByte<br />LDR R3,=UARTSTAT0<br />LDR R2,[R3]<br />TST R2,#&40<br />BEQ PutByte<br />LDR R3,=UTXBUF0<br />STR R0,[R3]<br />MOV PC,LR<br />Line1 DCB<br />&A,&D,"******************************************************************",0<br />Line2 DCB &A,&D,"Chinese Academy of Sciences,Institute of Automation,Complex System<br />Lab.",0<br />Line3 DCB &A,&D," ARM Development Board Based on Samsung ARM S3C4510B.",0<br />Line4 DCB<br />&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,&<br />A,&D,&A,&D,0<br />END
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