READMESCT is a usefull gnu tools to debug and trace serial port communicationHere are the documents help you to install and use uctI How to make and install sct 1 For linux platform    cp mk_linux Makefile    make    make install  2 For Sco-Unix platform    cp mk_sco Makefile    make    make install    II Quick guide to commands' of sct        At the time you run the sct,you may input the command     by the right at the prompt "=>". you may input "help"+command_name    for more detail. 1  "?"        to get command list 2  "help"         for detailed help for the command            usage: help command_name               eg: help sel                   get help of sel command 	 3  "stat" 	dsplay current port status 		    usage: stat 4  "sel" or "port"	select a serial device as current port 	    usage: sel device 			       eg: sel /dev/ttyS0 	 5  "frame"	set frameset 							    usage: frame rate,parity,databits,stopbits 			       eg: frame 9600,n,8,1	 6  "handshake" or "hs"	set handshake for port communication 	    usage: handshake [+/-] prototol			       eg: handshake +rts		            enable rts control			       eg: handshake -xonxoff	        		            disable xonxoff control	       eg: handshake none	            disable all hardware and fllow control	 7  "open"         open current port and active it 			    usage: open 		 8  "close" 	close current port and stop action 		    usage: close 	 9  "term" 	enter terminal mode	    usage: term  10 "echo" 	enter echo mode, reply all byte when received 	    usage: echo	 11 "setbuf"	set buffer data,10 buffers can use inall			    usage: setbuf buffer_no input_form 				       eg: setbuf 1 asc 					             set data of buf1 as ascii char			       eg: setbuf 2 hex 					             set data of buf2 hex code  12 "dispbuf" 	display buffers' info or buffer's data 			    usage: dispbuf [buffer_no]					       eg: dispbuf 					             get infomation ablout all buffers		       eg: dispbuf 3			 				             display data of buffer 3 by both ascii and hex form		 13 "clrbuf", 	clear the buffer						    usage: clrbuf buffer_no|all 				       eg: clrbuf 3						             clear buffer 3					       eg: clrbuf all                 				             clear all buffers 14 "loadbuf" 	load data to buffer from file 				    usage: loadbuf buffer_no filepath 				       eg: loadbuf 3 commu.dat				             load data to buffer 3 from file commu.dat		 15 "savebuf"		save data to file from buffer 				    usage: savebuf filepath buffer_no					       eg: savebuf commu.dat 3					             save data to file commu.dat from buffer 3 		 16 "copybuf"	copy buffer from one to another 				    usage: copybuf dest_buffer_no src_buffer_no 		       eg: copybuf 3 4 						             copy buffer 3 to buffer 4 17 "recv" 	recv data to buffer,10 buffers can use inall			    usage: recv bufffer_no 						       eg: recv 4 						             recv data to buffer 4	 18 "send" 	send buffer data,10 buffers can use inall 			    usage: send buffer_no 					       eg: send 1 						             send data from buffer 1 19 "sendrecv"	send the data from one buf and after that recv the data to another or same buf 			    usage: sendrecv send_buffer_no recv_buffer_no 			       eg: sendrecv 1 2						             send data from buffer 1 and after that recv data to buffer 2	       eg: sendrecv 1 1		     send data from buffer 1 and after that recover it with recved data