SH3_SCSSR2
while ((_reg_read_2(SH3_SCSSR2) & SCSSR2_TDFE) == 0)
_reg_write_1(SH3_SCSSR2, \
_reg_read_1(SH3_SCSSR2) & ~(SCSSR2_TDFE | SCSSR2_TEND)); \
r16 = _reg_read_2(SH3_SCSSR2);