C语言时尚编程百例.rar

終終終終終終終終終終終終終終終終終終 �inport, inportb, outport, outportb� <DOS.H> 景景景景景景景景景景景景景景景景景景 � inport reads a word from a hardware port � inportb reads a byte from a hardware port � outport outputs a word to a hardware port � outportb outputs a byte to a hardware port Declaration: � int inport(int portid); � unsigned char inportb(int portid); � void outport(int portid, int value); � void outportb(int portid, unsigned char value); Remarks: � inport works just like the 80x86 instruction IN. It reads the low byte of a word from portid, the high byte from portid + 2. � inportb is a macro that reads a byte � outport works just like the 80x86 instruction OUT. It writes the low byte of value to portid, the high byte to portid + 1. � outportb is a macro that writes value Argument� What It Is 怩怩怩怩退怩怩怩怩怩怩怩怩怩怩怩怩怩怩怩怩怩怩怩怩怩怩怩怩 portid � Inport port that inport and inportb read from; � outport port that outport and outportb write to value � Word that outport writes to portid; � byte that outportb writes to portid. If you call inportb or outportb when DOS.H has been included, they are treated as macros that expand to inline code. If you don't include DOS.H, or if you do include DOS.H and #undef the macro(s), you get the function(s) of the same name. Return Value: � inport and inportb return the value read � outport and outportb do not return Portability: � DOS � UNIX � ANSI C � C++ Only � � Yes � � � � 米怩怩虎怩怩怛怩怩怩怩虎怩怩怩怩征 See Also: inp, inpw outp, outpw Examples: inport example inportb example outport example outportb example