tcor.asm

文件为美军4800bps语音压缩编码标准在TI的DSP芯片TMS320C5X上的实时实现源代码。

	.version        50
	.mmregs
	;-------------
	.bss POLE_A,1
	.BSS POLE_Z,1
	.BSS POLE_XY,1
	;--------------
	.DATA
A	.INT 0c792h,03088h,0c934h,027c9h,0f22dh,01486h,0f3b3h,0971h,0ead5h,0a38h
Z	.LONG 0bdddh,0bdddh,0d806h,0e3d0h,0ed50h,0cdah,033dbh,04655h,044c0h,04221h,03e4bh,
XY	.INT 0fa3eh,0f6h,04fch,06bch,0fe5ah,0fdbfh,0fb9dh,0ffd8h,06h,036h,0fa63h,00h,07f8h,0feabh,0fea4h,0fff3h,0ff1bh,0fb65h,0ff22h,0182h,0211h,0409h,023h,0fff8h,042ch,0f780h,0fabbh,02b5h,0f44dh,0fc7fh,0adh,0267h,01b4h,0fc42h,0943h,0209h,0209h,022fh,0984h,0579h,0438h,0fe93h,0b1bh,057h,0fcafh,0fc1ah,02c9h,083h,0fc47h,0192h,00h,0fa17h,0fc10h,0589h,0fe09h,0fcf8h,07ceh,0379h,04b7h,030h
	CALL POLE_CON
HERE:	B HERE
;=================================
POLE_CON
	LAMM AR0
	PUSH
	LAMM AR1
	PUSH
	LAMM AR7
	PUSH
	LACC #13
	SAMM TREG1
;=================================
;  for (t = 0; t < len; t++)
;  { acc=xy[t]*0x2000l;
;=================================
	LACC #59
	SAMM AR7
	LAR AR0,#POLE_XY
POLE_FOR1
	MAR *,AR0
	LACC *,0,AR1
	SACB
;=================================
;    for (j = n; j > 0; j--)
;    { ax0=a[j]*0x2000;       p32=(long)ax0*(long)z[j];
;      acc -= p32;            z[j]=z[j-1];    }
;=================================
	LACC #9
	SAMM BRCR
	LAR AR1,#POLE_A+10
	LAR AR2,#POLE_Z+22
	RPTB POLE_FOR2-1
	  LT *
	  MPY
POLE_FOR2
;=================================
;=================================
;=================================
;=================================
;=================================
;=================================
;=================================
;=================================

;pole_con(float *a, 10, float *z, float *xy, 60)
;{
;/*  for (t = 0; t < len; t++)
;  { z[0] = xy[t];
;    for (j = n; j > 0; j--)
;    { z[0] -= a[j] * z[j];
;      z[j]  = z[j-1];    }
;    xy[t] = z[0];		  }*/
;  for (t = 0; t < len; t++)
;  { acc=xy[t]*0x2000l;
;    for (j = n; j > 0; j--)
;    { ax0=a[j]*0x2000;       p32=(long)ax0*(long)z[j];
;      acc -= p32;            z[j]=z[j-1];    }
;    acc>>=13;     z[0]=acc;     z[1]=acc;
;    if ( labs(acc) > 0x7fff )
;     { if(acc<0) acc=-0x8000l;
;       else acc=0x7fff;      }
;    xy[t]=acc;
;  } }

;=================================
	.end