dac_drv.lst

一个可作为mp3播放器固件的代码集,包括解码,播放,控制,任务管理等.

C51 COMPILER V7.50   DAC_DRV                                                               09/20/2005 21:47:38 PAGE 1   


C51 COMPILER V7.50, COMPILATION OF MODULE DAC_DRV
OBJECT MODULE PLACED IN dac_drv.obj
COMPILER INVOKED BY: e:\Keil\C51\BIN\C51.EXE lib_refd\dac\dac_drv.c OPTIMIZE(7,SPEED) BROWSE INCDIR(.\modules\system;.\;
                    -.\;.\lib_refd) DEFINE(KEIL) DEBUG OBJECTEXTEND PRINT(.\dac_drv.lst) OBJECT(dac_drv.obj)

line level    source

   1          /*C**************************************************************************
   2          * NAME:         dac_drv.c
   3          *----------------------------------------------------------------------------
   4          * Copyright (c) 2003 Atmel.
   5          *----------------------------------------------------------------------------
   6          * RELEASE:      snd1c-refd-nf-4_0_3      
   7          * REVISION:     1.5     
   8          *----------------------------------------------------------------------------
   9          * PURPOSE:
  10          * This file contains routines to address UDA1330ATS in L3 mode
  11          *
  12          *****************************************************************************/
  13          
  14          /*_____ I N C L U D E S ____________________________________________________*/
  15          
  16          #include "config.h"                         /* lib configuration header */
  17          #include "board.h"                          /* board definition */
  18          #include "dac_drv.h"                        /* dac driver definition */
  19          
  20          /*_____ M A C R O S ________________________________________________________*/
  21          
  22          
  23          /*_____ D E F I N I T I O N ________________________________________________*/
  24          
  25          /*_____ D E C L A R A T I O N ______________________________________________*/
  26          #ifdef DAC_L3MODE
  27          /*F**************************************************************************
  28          * NAME: dac_byte_send
  29          *----------------------------------------------------------------------------
  30          * PARAMS:
  31          *   b:   byte to send
  32          * return:
  33          *----------------------------------------------------------------------------
  34          * PURPOSE: 
  35          *   Serialize a data/cmd/addr byte on DAC_L3DATA & DAC_L3CLOCK pins.
  36          *----------------------------------------------------------------------------
  37          * NOTE:
  38          *   This function should only be used by dac_l3mode_send
  39          *----------------------------------------------------------------------------
  40          * REQUIREMENTS:
  41          *****************************************************************************/
  42          void dac_byte_send (Byte b)
  43          {
  44   1      Byte    c;
  45   1      
  46   1      for (c=8;c;c--)
  47   1        {
  48   2        DAC_L3DATA=(b&1); // practically 50% duty cycle
  49   2        DAC_L3CLOCK=0;
  50   2        b>>=1;
  51   2        DAC_L3CLOCK=1;    // data bit is sampled here (rising edge)
  52   2        }
  53   1      }
  54          
C51 COMPILER V7.50   DAC_DRV                                                               09/20/2005 21:47:38 PAGE 2   

  55          
  56          /*F**************************************************************************
  57          * NAME: dac_l3mode_send
  58          *----------------------------------------------------------------------------
  59          * PARAMS:
  60          *   addr:   logical address of the chip (000101xxb for UDA1330)
  61          *   b:      data/cmd byte to send
  62          * return:
  63          *----------------------------------------------------------------------------
  64          * PURPOSE: 
  65          *   Send a L3-mode command to the DAC UDA1330
  66          *----------------------------------------------------------------------------
  67          * NOTE:
  68          *   This function improve the song quality (low level, decrease signal/noise).
  69          *----------------------------------------------------------------------------
  70          * REQUIREMENTS:
  71          *   Only tested with UDA1330ATS
  72          *****************************************************************************/
  73          void dac_l3mode_send (Byte addr,Byte b)
  74          {
  75   1      DAC_TEST=0;     // be carefull ! if DAC_TEST is set with DAC_APPSEL not set, I/O of UDA1330 change a lot
  76   1      DAC_APPSEL=0;   // Turn DAC in L3 mode
  77   1      DAC_L3MODE=1;   
  78   1      DAC_L3CLOCK=1;
  79   1      DAC_L3DATA=1;   // Normal state, basically, those three pins are already set
  80   1      // Begin Addr transfer
  81   1      DAC_L3MODE=0;
  82   1      dac_byte_send(addr);
  83   1      // Begin Data/Cmd transfer
  84   1      DAC_L3MODE=1;
  85   1      dac_byte_send(b);
  86   1      // Ack end of data/cmd transfer
  87   1      DAC_L3MODE=0;
  88   1      DAC_L3MODE=1;
  89   1      }
  90          
  91          /*F**************************************************************************
  92          * NAME: dac_set_vol
  93          *----------------------------------------------------------------------------
  94          * PARAMS:
  95          *
  96          * return:
  97          *----------------------------------------------------------------------------
  98          * PURPOSE: 
  99          *   Use the DAC to modify song level.
 100          *----------------------------------------------------------------------------
 101          * NOTE:
 102          *   This function must be call each time mp3_volume is changed
 103          *----------------------------------------------------------------------------
 104          * REQUIREMENTS:
 105          *****************************************************************************/
 106          void dac_set_vol (Byte volume)
 107          {
 108   1      if (volume>=32) volume=16; // security !
 109   1      if (volume<24)
 110   1        {
 111   2        MP3VOL = MP3VOR = 15;
 112   2        dac_l3mode_send(DAC_L3I_ADDR,64-(volume<<1)-volume+(volume>>2));
 113   2        }
 114   1      else
 115   1        {
 116   2        MP3VOL = MP3VOR = 15 + ((volume-23)<<1);
C51 COMPILER V7.50   DAC_DRV                                                               09/20/2005 21:47:38 PAGE 3   

 117   2        dac_l3mode_send(DAC_L3I_ADDR,0);
 118   2        }
 119   1      }
 120          
 121          #endif
 122          


MODULE INFORMATION:   STATIC OVERLAYABLE
   CODE SIZE        =    108    ----
   CONSTANT SIZE    =   ----    ----
   XDATA SIZE       =   ----    ----
   PDATA SIZE       =   ----    ----
   DATA SIZE        =   ----    ----
   IDATA SIZE       =   ----    ----
   BIT SIZE         =   ----    ----
END OF MODULE INFORMATION.


C51 COMPILATION COMPLETE.  0 WARNING(S),  0 ERROR(S)