public void illegal_1()
    {
        Z80.PC.AddD(-1);
        if( errorlog!=null )
            fprintf(errorlog, "Z80#%d ill. opcode $%02x $%02x\n",cpu_getactivecpu(), cpu_readop((Z80.PC.D-1)&0xffff), cpu_readop(Z80.PC.D));
    }