DSCR_SRC1_STS
src1 |= DSCR_SRC1_STS(DSCR_xTS_SIZE1);
src1 |= DSCR_SRC1_STS(DSCR_xTS_SIZE2);
src1 |= DSCR_SRC1_STS(DSCR_xTS_SIZE4);
src1 |= DSCR_SRC1_STS(DSCR_xTS_SIZE8);