GNU ARM汇编--(七)s3c2440的串口控制

1. ,=GPBDAT
3. blclock_setup
4. bluart_init
5. bldelay
8. ldrlr,=loop
9. @bluart_testdd
10. ldrpc,_uart_test
12. _uart_test:.worduart_test
13. loop:
14. bloop@死循环
16. ledloop:
18. ldrr1,=0x1c0
19. strr1,[r2]
20. bldelay
22. ldrr1,=0x1a0
23. strr1,[r2]
24. bldelay
26. ldrr1,=0x160
27. strr1,[r2]
28. bldelay
30. ldrr1,=0x0e0
31. strr1,[r2]
32. bldelay
35. bledloop
37. clock_setup:
39. ldrr0,=LOCKTIME
40. ldrr1,=0xffffffff
41. strr1,[r0]
43. ldrr0,=CLKdivN
44. ldrr1,=(divN_UPLL<3)|(HdivN<1)|(PdivN<0)
45. strr1,[r0]
47. ldrr0,=UPLLCON
48. ldrr1,=(U_Mdiv<12)|(U_Pdiv<4)|(U_Sdiv<0)@Fin=12MUPLL=48M
49. strr1,[r0]
50. nop
51. nop
52. nop
53. nop
54. nop
55. nop
56. nop
57. ldrr0,=MPLLCON
58. ldrr1,=(M_Mdiv<12)|(M_Pdiv<4)|(M_Sdiv<0)@Fin=12MFCLK=400M
59. strr1,[r0]
63. movpc,lr
65. uart_init:
66. ldrr0,=GPHCON
67. ldrr1,=0x2aaaa@配置GPIO复用规则为串口
68. strr1,[r0]
70. ldrr0,=ULCON0
71. ldrr1,=(IR_MODE<6)|(Parity_Mode<3)|(Num_of_stop_bit<2)|(Word_length<0)@
72. strr1,[r0]
74. ldrr0,=UCON0
75. 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)
76. strr1,[r0]
78. ldrr0,=UFCON0
79. ldrr1,=(Tx_FIFO_Trig_Level<6)|(Rx_FIFO_Trig_Level<4)|(Tx_FIFO_Reset<2)|(Rx_FIFO_Reset<1)|(FIFO_Enable<0)@
80. strr1,[r0]
82. ldrr0,=UBRdiv0
83. ldrr1,=(UBRdiv<0)
84. strr1,[r0]
86. movpc,lr
88. delay:
89. @ldrr3,=0x4ffffff
90. ldrr3,=0xfffff
92. delay1:
93. subr3,r3,#1
95. cmpr3,#0x0
97. bnedelay1
99. movpc,lr

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. }

[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)

中断模式还没写,这个等到后面全面研究uboot的时候再回头看,uboot用哪种模式,应该就说明那种方式好,到时侯再实现吧