新聞中心

EEPW首頁(yè) > 嵌入式系統(tǒng) > 設(shè)計(jì)應(yīng)用 > GNU ARM匯編--(七)s3c2440的串口控制

GNU ARM匯編--(七)s3c2440的串口控制

作者： 時(shí)間：2016-11-26 來(lái)源：網(wǎng)絡(luò) 收藏
  • .global_main
  • _main:
  • ldrr0,=GPBCON
  • ldrr1,=0x15400
  • strr1,[r0]
  • ldrr2,=GPBDAT
  • blclock_setup
  • bluart_init
  • bldelay
  • ldrlr,=loop
  • @bluart_testdd
  • ldrpc,_uart_test
  • _uart_test:.worduart_test
  • loop:
  • bloop@死循環(huán)
  • ledloop:
  • ldrr1,=0x1c0
  • strr1,[r2]
  • bldelay
  • ldrr1,=0x1a0
  • strr1,[r2]
  • bldelay
  • ldrr1,=0x160
  • strr1,[r2]
  • bldelay
  • ldrr1,=0x0e0
  • strr1,[r2]
  • bldelay
  • bledloop
  • clock_setup:
  • ldrr0,=LOCKTIME
  • ldrr1,=0xffffffff
  • strr1,[r0]
  • ldrr0,=CLKDIVN
  • ldrr1,=(DIVN_UPLL<<3)|(HDIVN<<1)|(PDIVN<<0)
  • strr1,[r0]
  • ldrr0,=UPLLCON
  • ldrr1,=(U_MDIV<<12)|(U_PDIV<<4)|(U_SDIV<<0)@Fin=12MUPLL=48M
  • strr1,[r0]
  • nop
  • nop
  • nop
  • nop
  • nop
  • nop
  • nop
  • ldrr0,=MPLLCON
  • ldrr1,=(M_MDIV<<12)|(M_PDIV<<4)|(M_SDIV<<0)@Fin=12MFCLK=400M
  • strr1,[r0]
  • movpc,lr
  • uart_init:
  • ldrr0,=GPHCON
  • ldrr1,=0x2aaaa@配置GPIO復(fù)用規(guī)則為串口
  • strr1,[r0]
  • ldrr0,=ULCON0
  • ldrr1,=(IR_MODE<<6)|(Parity_Mode<<3)|(Num_of_stop_bit<<2)|(Word_length<<0)@
  • strr1,[r0]
  • ldrr0,=UCON0
  • ldrr1,=(FCLK_Div<<12)|(Clk_select<<10)|(Tx_Int_Type<<9)|(Rx_Int_Type<<8)|(Rx_Timeout<<7)|(Rx_Error_Stat_Int<<6)|(Loopback_Mode<<5)|(Break_Sig<<4)|(Tx_Mode<<2)|(Rx_Mode<<0)
  • strr1,[r0]
  • ldrr0,=UFCON0
  • ldrr1,=(Tx_FIFO_Trig_Level<<6)|(Rx_FIFO_Trig_Level<<4)|(Tx_FIFO_Reset<<2)|(Rx_FIFO_Reset<<1)|(FIFO_Enable<<0)@
  • strr1,[r0]
  • ldrr0,=UBRDIV0
  • ldrr1,=(UBRDIV<<0)
  • strr1,[r0]
  • movpc,lr
  • delay:
  • @ldrr3,=0x4ffffff
  • ldrr3,=0xfffff
  • delay1:
  • subr3,r3,#1
  • cmpr3,#0x0
  • bnedelay1
  • movpc,lr

    • UART的測(cè)試代碼用C寫(xiě)的:

    本文引用地址：http://m.butianyuan.cn/article/201611/321724.htm

    uart_test.c:

    [cpp]view plaincopy
    1. #include"uart_test.h"
    3. charuart_GetByte(void)
    4. {
    5. while(!(rUTRSTAT0&0x1));//WaituntilTHRisempty.
    6. returnRdURXH0();
    7. }
    10. voiduart_GetString(char*pt)
    11. {
    12. while(*pt)
    13. uart_GetByte();
    14. }
    17. voiduart_SendByte(intdata)
    18. {
    20. if(data==)
    21. {
    22. while(!(rUTRSTAT0&0x2));
    23. WrUTXH0();
    24. }
    25. while(!(rUTRSTAT0&0x2));//WaituntilTHRisempty.
    26. WrUTXH0(data);
    28. }
    30. //====================================================================
    31. voiduart_SendString(char*pt)
    32. {
    33. while(*pt)
    34. uart_SendByte(*pt++);
    35. }
    38. voiduart_test(void)
    39. {
    41. charstr[20]="helloworld";
    42. inta=97;
    43. //while(1)
    44. //uart_SendByte(a);
    45. uart_SendString(str);
    46. chars=uart_GetByte();
    47. //if(s==a)
    48. if(s==97)
    49. rGPBDAT=0x1c0;
    50. //uart_SendByte(a);
    51. //uart_SendByte(97);
    52. //uart_SendByte(a);
    53. uart_SendByte((int)s);
    54. uart_SendByte((int)s);
    55. }
    uart_test.h:

    [cpp]view plaincopy
    1. //#defineWrUTXH0(ch)(*(volatileunsignedchar*)0x50000023)=(unsignedchar)(ch)
    2. #defineWrUTXH0(ch)(*(volatileunsignedchar*)0x50000020)=(unsignedchar)(ch)
    3. #defineRdURXH0()(*(volatileunsignedchar*)0x50000024)
    4. #definerUTRSTAT0(*(volatileunsigned*)0x50000010)//UART0Tx/Rxstatus
    6. #definerGPBDAT(*(volatileunsigned*)0x56000014)


    到此,使用串口的輪循模式,可以實(shí)現(xiàn)串口的正常收發(fā)功能了～～

    中斷模式還沒(méi)寫(xiě),這個(gè)等到后面全面研究uboot的時(shí)候再回頭看,uboot用哪種模式,應(yīng)該就說(shuō)明那種方式好,到時(shí)侯再實(shí)現(xiàn)吧
    上一頁(yè) 1 2 3 下一頁(yè)

    關(guān)鍵詞： ARM匯編s3c2440串口控

    評(píng)論


    相關(guān)推薦

    技術(shù)專區(qū)

    關(guān)閉