IREG_CLK_BITS
on &= IREG_CLK_BITS;
off &= IREG_CLK_BITS;
interreg = *interrupt_reg & IREG_CLK_BITS;
single_inst_bclr_b(*interrupt_reg, IREG_CLK_BITS);
on &= IREG_CLK_BITS;
off &= IREG_CLK_BITS;
interreg = *interrupt_reg & IREG_CLK_BITS;
single_inst_bclr_b(*interrupt_reg, IREG_CLK_BITS);