xeye_ atsu
/
RiceGolombDPCM_Player
For BU9480F D-A Conv.
main.cpp@3:64c3ed0fc4b4, 2010-09-11 (annotated)
- Committer:
- lynxeyed_atsu
- Date:
- Sat Sep 11 11:23:26 2010 +0000
- Revision:
- 3:64c3ed0fc4b4
- Parent:
- 2:baf5bf51cd28
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
lynxeyed_atsu | 0:805cffac956b | 1 | /* DPCM & Rice Golomb Lossless Audio Player and Realtime encoder */ |
lynxeyed_atsu | 1:02bfb013660c | 2 | #include "SDHCFileSystem.h" |
lynxeyed_atsu | 0:805cffac956b | 3 | #include "mbed.h" |
lynxeyed_atsu | 0:805cffac956b | 4 | #include "string" |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 5 | #include "_bitio.h" |
lynxeyed_atsu | 1:02bfb013660c | 6 | |
lynxeyed_atsu | 0:805cffac956b | 7 | //FILE *infp,*outfp; |
lynxeyed_atsu | 1:02bfb013660c | 8 | SDFileSystem sd(p5, p6, p7, p8, "sd"); |
lynxeyed_atsu | 0:805cffac956b | 9 | DigitalOut led1(LED1); |
lynxeyed_atsu | 0:805cffac956b | 10 | DigitalOut led2(LED2); |
lynxeyed_atsu | 0:805cffac956b | 11 | AnalogOut DACout(p18); |
lynxeyed_atsu | 0:805cffac956b | 12 | Ticker tick; |
lynxeyed_atsu | 0:805cffac956b | 13 | |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 14 | // BU9480F define |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 15 | SPI bu9480f(p11,p12,p13); |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 16 | DigitalOut LRCLK(p14); |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 17 | // BU9480F define.end |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 18 | |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 19 | |
lynxeyed_atsu | 0:805cffac956b | 20 | // a FIFO for the DAC |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 21 | #define TXFIFO_FULL 1 |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 22 | #define RAM_LENGTH 8192//8192 |
lynxeyed_atsu | 1:02bfb013660c | 23 | #define RAM_LIMIT (RAM_LENGTH - 1) |
lynxeyed_atsu | 1:02bfb013660c | 24 | volatile short DAC_fifo[RAM_LENGTH]; |
lynxeyed_atsu | 0:805cffac956b | 25 | volatile short DAC_wptr=0; |
lynxeyed_atsu | 0:805cffac956b | 26 | volatile short DAC_rptr=0; |
lynxeyed_atsu | 0:805cffac956b | 27 | volatile short DAC_on; |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 28 | volatile short DAC_diff=0; |
lynxeyed_atsu | 0:805cffac956b | 29 | |
lynxeyed_atsu | 0:805cffac956b | 30 | void dac_out() |
lynxeyed_atsu | 0:805cffac956b | 31 | { |
lynxeyed_atsu | 0:805cffac956b | 32 | // printf("\t%d\r\n",DAC_diff); |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 33 | if (DAC_diff > 1) { |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 34 | led2 = 0; |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 35 | |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 36 | LRCLK = 0; |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 37 | bu9480f.write(DAC_fifo[DAC_rptr++]); |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 38 | DAC_rptr &= RAM_LIMIT; |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 39 | |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 40 | LRCLK = 1; |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 41 | bu9480f.write(DAC_fifo[DAC_rptr++]); |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 42 | DAC_rptr &= RAM_LIMIT; |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 43 | |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 44 | DAC_diff-=2; |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 45 | |
lynxeyed_atsu | 0:805cffac956b | 46 | }else led2 = 1; |
lynxeyed_atsu | 0:805cffac956b | 47 | } |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 48 | |
lynxeyed_atsu | 0:805cffac956b | 49 | void encode(long int n){ |
lynxeyed_atsu | 0:805cffac956b | 50 | int zero_shift = 0; |
lynxeyed_atsu | 0:805cffac956b | 51 | |
lynxeyed_atsu | 0:805cffac956b | 52 | if(n < 0){ |
lynxeyed_atsu | 0:805cffac956b | 53 | putbit(0); // sign (put 0:if n as negative) |
lynxeyed_atsu | 0:805cffac956b | 54 | n = -n; // n = abs(n) |
lynxeyed_atsu | 0:805cffac956b | 55 | //printf("\t 0"); |
lynxeyed_atsu | 0:805cffac956b | 56 | } |
lynxeyed_atsu | 0:805cffac956b | 57 | else{ |
lynxeyed_atsu | 0:805cffac956b | 58 | putbit(1); // sign (put 1:if n as positive) |
lynxeyed_atsu | 0:805cffac956b | 59 | //printf("\t 1"); |
lynxeyed_atsu | 0:805cffac956b | 60 | } |
lynxeyed_atsu | 0:805cffac956b | 61 | zero_shift = (n >> (k)); |
lynxeyed_atsu | 0:805cffac956b | 62 | //printf("\t shift= %d",zero_shift); |
lynxeyed_atsu | 0:805cffac956b | 63 | while(zero_shift > 0){ |
lynxeyed_atsu | 0:805cffac956b | 64 | |
lynxeyed_atsu | 0:805cffac956b | 65 | zero_shift--; |
lynxeyed_atsu | 0:805cffac956b | 66 | putbit(0); |
lynxeyed_atsu | 0:805cffac956b | 67 | } // put n/(2^k) 0's |
lynxeyed_atsu | 0:805cffac956b | 68 | |
lynxeyed_atsu | 0:805cffac956b | 69 | putbit(1); // terminating "1" |
lynxeyed_atsu | 0:805cffac956b | 70 | putbits(k,rightbits(k,n)); |
lynxeyed_atsu | 0:805cffac956b | 71 | //printf("\t finish= %d \r\n",(n & ((1U<<k)-1))); |
lynxeyed_atsu | 0:805cffac956b | 72 | } |
lynxeyed_atsu | 0:805cffac956b | 73 | |
lynxeyed_atsu | 0:805cffac956b | 74 | |
lynxeyed_atsu | 0:805cffac956b | 75 | |
lynxeyed_atsu | 0:805cffac956b | 76 | void decode(void){ |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 77 | //short dac_data; |
lynxeyed_atsu | 0:805cffac956b | 78 | long int decode_buff; |
lynxeyed_atsu | 0:805cffac956b | 79 | short diff,diff2; |
lynxeyed_atsu | 0:805cffac956b | 80 | unsigned int buff_sign,zero_shift; |
lynxeyed_atsu | 0:805cffac956b | 81 | //char flag; |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 82 | |
lynxeyed_atsu | 0:805cffac956b | 83 | diff = 0; |
lynxeyed_atsu | 0:805cffac956b | 84 | diff2 = 0; |
lynxeyed_atsu | 0:805cffac956b | 85 | // get sign(1 for positive, 0 for negative) |
lynxeyed_atsu | 0:805cffac956b | 86 | while(1){ |
lynxeyed_atsu | 0:805cffac956b | 87 | |
lynxeyed_atsu | 0:805cffac956b | 88 | if((buff_sign = getbit())==OVERRUN)break; |
lynxeyed_atsu | 0:805cffac956b | 89 | zero_shift = 0; |
lynxeyed_atsu | 0:805cffac956b | 90 | while(getbit()==0)zero_shift++; |
lynxeyed_atsu | 0:805cffac956b | 91 | |
lynxeyed_atsu | 0:805cffac956b | 92 | decode_buff = (signed int)((1U << k)*zero_shift); |
lynxeyed_atsu | 0:805cffac956b | 93 | decode_buff += (getbits(k)); |
lynxeyed_atsu | 0:805cffac956b | 94 | |
lynxeyed_atsu | 0:805cffac956b | 95 | if(!buff_sign)decode_buff =- decode_buff; |
lynxeyed_atsu | 0:805cffac956b | 96 | /* return decode_buff; */ |
lynxeyed_atsu | 0:805cffac956b | 97 | diff =(diff + decode_buff); |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 98 | DAC_fifo[DAC_wptr++]=(short)diff; |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 99 | DAC_wptr &= RAM_LIMIT; |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 100 | //DAC_diff++; |
lynxeyed_atsu | 1:02bfb013660c | 101 | while (DAC_diff > RAM_LIMIT){ |
lynxeyed_atsu | 0:805cffac956b | 102 | led1 = 1; |
lynxeyed_atsu | 0:805cffac956b | 103 | } //wait |
lynxeyed_atsu | 0:805cffac956b | 104 | led1=0; |
lynxeyed_atsu | 0:805cffac956b | 105 | |
lynxeyed_atsu | 0:805cffac956b | 106 | if((buff_sign = getbit())==OVERRUN)break; |
lynxeyed_atsu | 0:805cffac956b | 107 | zero_shift = 0; |
lynxeyed_atsu | 0:805cffac956b | 108 | while(getbit()==0)zero_shift++; |
lynxeyed_atsu | 0:805cffac956b | 109 | |
lynxeyed_atsu | 0:805cffac956b | 110 | decode_buff = (signed int)((1U << k)*zero_shift); |
lynxeyed_atsu | 0:805cffac956b | 111 | decode_buff += (getbits(k)); |
lynxeyed_atsu | 0:805cffac956b | 112 | |
lynxeyed_atsu | 0:805cffac956b | 113 | if(!buff_sign)decode_buff =- decode_buff; |
lynxeyed_atsu | 0:805cffac956b | 114 | /* return decode_buff; */ |
lynxeyed_atsu | 0:805cffac956b | 115 | diff2 =(diff2 + decode_buff); |
lynxeyed_atsu | 0:805cffac956b | 116 | |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 117 | DAC_fifo[DAC_wptr++]=(short)diff2; |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 118 | DAC_wptr &= RAM_LIMIT; |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 119 | DAC_diff+=2; |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 120 | |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 121 | while (DAC_diff > RAM_LIMIT){ |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 122 | led1 = 1; |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 123 | } //wait |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 124 | led1=0; |
lynxeyed_atsu | 0:805cffac956b | 125 | |
lynxeyed_atsu | 0:805cffac956b | 126 | |
lynxeyed_atsu | 0:805cffac956b | 127 | |
lynxeyed_atsu | 0:805cffac956b | 128 | } |
lynxeyed_atsu | 0:805cffac956b | 129 | } |
lynxeyed_atsu | 1:02bfb013660c | 130 | |
lynxeyed_atsu | 1:02bfb013660c | 131 | |
lynxeyed_atsu | 1:02bfb013660c | 132 | int main() { |
lynxeyed_atsu | 1:02bfb013660c | 133 | |
lynxeyed_atsu | 1:02bfb013660c | 134 | |
lynxeyed_atsu | 1:02bfb013660c | 135 | if ( NULL == (infp = fopen( "/sd/test.rgm", "rb" )) ) { |
lynxeyed_atsu | 1:02bfb013660c | 136 | printf( "\r\nError: The message file cannot be accessed\r\n" ); |
lynxeyed_atsu | 1:02bfb013660c | 137 | return -1; |
lynxeyed_atsu | 1:02bfb013660c | 138 | } |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 139 | // bu9480f init |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 140 | bu9480f.format(16,0); |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 141 | bu9480f.frequency(16000000); //16MHz |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 142 | // bu9480f init.end |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 143 | |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 144 | |
lynxeyed_atsu | 3:64c3ed0fc4b4 | 145 | tick.attach_us(&dac_out, 41); //set 24.000kHz sampling data |
lynxeyed_atsu | 1:02bfb013660c | 146 | decode(); |
lynxeyed_atsu | 1:02bfb013660c | 147 | tick.detach(); |
lynxeyed_atsu | 1:02bfb013660c | 148 | |
lynxeyed_atsu | 1:02bfb013660c | 149 | fclose( infp ); |
lynxeyed_atsu | 1:02bfb013660c | 150 | //fclose( outfp ); |
lynxeyed_atsu | 1:02bfb013660c | 151 | |
lynxeyed_atsu | 1:02bfb013660c | 152 | |
lynxeyed_atsu | 1:02bfb013660c | 153 | |
lynxeyed_atsu | 1:02bfb013660c | 154 | while (1); |
lynxeyed_atsu | 1:02bfb013660c | 155 | } |
lynxeyed_atsu | 1:02bfb013660c | 156 |