i2cregin.tdf

来自「基于fpga的屏幕测试程序」· TDF 代码 · 共 61 行

INCLUDE "I2CREGIN";

PARAMETERS
   (
   SUBADDRESS=0,
   SUBADDRESSBITS=8,
   INBITS=8
   );

CONSTANT I2CBUSWIDTH = SUBADDRESSBITS+20;

SUBDESIGN i2cRegIn
   (
   i2cBusIn[I2CBUSWIDTH-1..0]: INPUT;
   i2cBusOut[I2CBUSWIDTH-1..0]: OUTPUT;
   in[INBITS-1..0]: INPUT;
   )

VARIABLE
   IF (INBITS>8) GENERATE
      highI2cInReg: i2cRegIn WITH (SUBADDRESS=SUBADDRESS+1,SUBADDRESSBITS=SUBADDRESSBITS,INBITS=INBITS-8);
      lowI2cInReg:  i2cRegIn WITH (SUBADDRESS=SUBADDRESS  ,SUBADDRESSBITS=SUBADDRESSBITS,INBITS=8);
   END GENERATE;
   IF (INBITS<=8) GENERATE
      reg[INBITS-1..0]: DFF;
      add[SUBADDRESSBITS-1..0]: NODE;
      clk,rd: NODE;
      sel: SOFT;
   END GENERATE;

BEGIN
IF (INBITS>8) GENERATE
   lowI2CInReg.i2cBusIn[]=i2cBusIn[];
   highI2CInReg.i2cBusIn[]=lowI2CInReg.i2cBusOut[];   
   i2cBusOut[]=highI2CinReg.i2cBusOut[];
   lowI2CinReg.in[]=in[7..0];
   highI2CinReg.in[]=in[INBITS-1..8];
END GENERATE;

IF (INBITS<=8) GENERATE
   clk=i2cBusIn[0];
   rd=i2cBusIn[2];
   add[]=i2cBusIn[I2CBUSWIDTH-1..20];
   sel=(rd & add[]==SUBADDRESS);
   reg[].clk=clk;
   reg[].d=in[];
   IF (INBITS<8) GENERATE
      i2cBusOut[19..12]=i2cBusIn[19..12] & ((0,reg[]) # !sel);
   END GENERATE;
   IF (INBITS==8) GENERATE
      i2cBusOut[19..12]=i2cBusIn[19..12] & (reg[] # !sel);
   END GENERATE;
   i2cBusOut[11..0]=i2cBusIn[11..0];
   i2cBusOut[I2CBUSWIDTH-1..20]=i2cBusIn[I2CBUSWIDTH-1..20];
END GENERATE;

END;