mii.lst

以C语言利用PIC12C508A读写MII Phy的寄存器

     1: 
     2: /************************************************************   
     3:  *      Processer : Microchip PIC12C508A                                                        *
     4:  *      Compiler : Hi-TECH PICC 8.01 PL3                                                        *
     5:  *      Writer : Jason Kuo                                                                                      *
     6:  *      Description : It can read/write MII Phy Register                                        *
     7:  *************************************************************/ 
     8: #include <pic.h>
     9: 
    10: typedef unsigned char   u8;
    11: typedef unsigned int    u16;
    12: 
    13: #define MDC             GP0
    14: #define MDIO            GP1
    15: 
    16: u16 rx_buf,tx_buf;
    17: 
    18: void    InitPIC(void);
    19: void Mdc_Pulse(void);  /*Clock line */
    20: void Preamble(void);
    21: void Send_Addr(char Data);
    22: void PHY_Addr(char phy_id);
    23: void Reg_Addr(char reg_addr);
    24: void WriteData(void);
    25: void ReadData(void);
    26: void Idle(void);
    27: void Mii_Read(char phy_id,char reg_addr);
    28: void Mii_Write(char phy_id,char reg_addr);
    29: 
    30: //u16 rx_buf,tx_buf;
    31: 
    32: 
    33: /*******************************************************/
    34: void main(void)
    35: {
    36:      u8 regnum;
    37:      
    38:      InitPIC();
    39:      for (regnum = 0; regnum < 10; regnum++)
    40:      {
    41:                 Mii_Read(0x00, regnum);
    42:                 tx_buf = rx_buf;
    43:                 Mii_Write(0x00, regnum);
    44:      }
    45: 
    46: }
    47: 
    48: void    InitPIC(void)
    49: {
    50:     OPTION = (GPWU | GPPU | PS2 | PS1 | PS0);
    51:     TRIS = 0x10;        
    52:     MDC = 1;
    53:     MDIO = 0;
    54: }
    55: 
    56: 
    57: void Mdc_Pulse(void)  /*Clock line */
    58: {
    59:      MDC = 1;
    60:      MDC = 1;
    61:      MDC = 0;
    62: }
    63: 
    64: void Preamble(void)
    65: {
    66:     char i;
    67: 
    68:     MDIO = 1;
    69:     /* Transmit Preamble 11....11(32 bits) */
    70:     for(i=0 ; i < 32 ; i++)
    71:         Mdc_Pulse();
    72:     /* Transmit Start of Frame '01' */
    73:     MDIO = 0;
    74:     Mdc_Pulse();
    75:     MDIO = 1;
    76:     Mdc_Pulse();
    77: }
    78: 
    79: void Send_Addr(char Data)
    80: {
    81:     char i;
    82: 
    83:     for(i = 0; i < 5; i++)
    84:     {
    85:         if(Data & 0x10)
    86:             MDIO = 1;
    87:         else
    88:             MDIO = 0;
    89:         Mdc_Pulse();
    90:         Data <<= 1;
    91:     }
    92: }
    93: 
    94: void PHY_Addr(char phy_id)
    95: {
    96:     /* Transmit Selected Address */
    97:     Send_Addr(phy_id);
    98: }
    99: 
   100: void Reg_Addr(char reg_addr)
   101: {
   102:   /* Transmit Selected register*/
   103:     Send_Addr(reg_addr);
   104: }
   105: 
   106: void WriteData(void)
   107: {
   108:     char i;
   109:     unsigned int Temp;
   110:     Temp = 0x8000;
   111:     for ( i = 0;i < 16; i++)
   112:     {
   113:       if(tx_buf & Temp)
   114:           MDIO = 1;
   115:       else
   116:          MDIO = 0;
   117:       Mdc_Pulse();
   118:       Temp >>= 1;
   119:     }
   120: }
   121: 
   122: void ReadData(void)
   123: {
   124:     char i;
   125:     rx_buf = 0x0000;
   126:     for ( i = 0;i < 16; i++)
   127:     {
   128:         Mdc_Pulse();
   129:         if (MDIO == 1)
   130:             rx_buf |= 0x0001;
   131:         if (i < 15)
   132:             rx_buf <<= 1;
   133:     }
   134: }
   135: 
   136: void Idle(void)
   137: {
   138:     MDIO = 1;
   139:     Mdc_Pulse();
   140: }
   141: 
   142: void Mii_Read(char phy_id,char reg_addr)
   143: {
   144: 
   145:     rx_buf = 0x0000;
   146:     Preamble();
   147:     /*OP Code 10*/
   148:     MDIO = 1;
   149:     Mdc_Pulse();
   150:     MDIO = 0;
   151:     Mdc_Pulse();
   152:     PHY_Addr(phy_id);
   153:     Reg_Addr(reg_addr);
   154:     /*Turnaround Z*/
   155:     MDIO = 1;
   156:     Mdc_Pulse();
   157:     ReadData();
   158:     Idle();
   159: }
   160: 
   161: void Mii_Write(char phy_id,char reg_addr)
   162: {
   163:     Preamble();
   164:     /*OP Code 01*/
   165:     MDIO = 0;
   166:     Mdc_Pulse();
   167:     MDIO = 1;
   168:     Mdc_Pulse();
   169:     PHY_Addr(phy_id);
   170:     Reg_Addr(reg_addr);
   171:     /*Turnaround 10*/
   172:     MDIO = 1;
   173:     Mdc_Pulse();
   174:     MDIO = 0;
   175:     Mdc_Pulse();
   176:     WriteData();
   177:     Idle();
   178: }