1 %%convert a sinal data into hex file format 2 % data format:16bit  3 % signal length: less than 2^24-1 4 % author: Yang Li yangli0534@gmail.com 5 % data:2015.01.27 6  7 clear all; 8 close all; 9 clc;10 11 %% fixed point or binary16 float point12 fixed=1;13 %% generate a signal waveform14 %15 T=10;%time length16 fs=1e3;%sample rate17 N=10000;18 Period=N/fs/10;19 f=1/Period;20 t=linspace(0,(N-1)/fs,N);21 22 %data=http://www.mamicode.com/1:2^5-1; 23 data= http://www.mamicode.com/sin(2*pi*f*t) +(rand(1,N)-0.5)/10;24 % data=http://www.mamicode.com/mod(50000*t,1000);25 % plot(t,data)26 dataBits=16;27 byteBits=8;28 29 %% convert into 16 bits fixed point number30 if fixed == 131     maximum=max(abs(data));%maximum of absolute signal 32     scale=(2^15-1)/maximum;%scale 33     data=http://www.mamicode.com/round(data*scale);34     for i=1:1:length(data)35         if data(i) <0 36             data(i) =2^16-abs(data(i)) ;37         end38     end39 end40 %% write41 fh=fopen(‘data.hex‘,‘w‘);%open a new file (file path, file name)42 bytesEveryRow=16;%write 16 bytes every row43 dataEveryRow=bytesEveryRow/(dataBits/byteBits);%number of data every row44 lengthData=http://www.mamicode.com/length(data);%length of signal data45 rowLengths=ceil(lengthData/dataEveryRow);%number of rows of the file to be written46 47 for i=1:rowLengths % write a row each time48     if(mod(i,hex2dec(‘1000‘))==1)49         baseaddr=dec2hex(floor(i/hex2dec(‘1000‘)),4);50         checkSum=6+hex2dec(baseaddr(1:2))+hex2dec(baseaddr(3:4));51          checkSum=(dec2hex(bitand(256-mod(checkSum,256),255),2));52         fprintf(fh,[‘:02000004‘,baseaddr,checkSum,13,10]);%产生HEX码(end-1:end)53     54     end55     checkSum=0;56     addr=dec2hex(mod((i-1)*16,hex2dec(‘10000‘)),4);%the start address of this row57     checkSum=hex2dec(addr(1:2))+hex2dec(addr(3:4));58     if i*dataEveryRow <lengthData %  numbers of data to be written greater than dataEveryRow59         dataRow=dataEveryRow;60         dataHex=‘‘;61         for j=8*(i-1)+1:1:8*(i)            62             if fixed == 1%                63                 dataHexCurr=dec2hex(data(j),4);%16 bits fixed point64              else65                 dataHexCurr=num2binary16hex(data(j));%number format: 16bits floatIEEE 754 half precison float point standard,result is a hex format66              end67             checkSum=checkSum+hex2dec(dataHexCurr(1:2))+hex2dec(dataHexCurr(3:4));68             dataHex=strcat(dataHex,dataHexCurr);69         end    70             71     else72          dataHex=‘‘;73          dataRow =lengthData-(rowLengths-1)*dataEveryRow;74         for j=(rowLengths-1)*dataEveryRow+1:1:lengthData            75              if fixed == 1% 76                 dataHexCurr=dec2hex(data(j),4);%16 bits fixed point77              else78                 dataHexCurr=num2binary16hex(data(j));%number format: 16bits floatIEEE 754 half precison float point standard,result is a hex format79              end  80             checkSum=checkSum+hex2dec(dataHexCurr(1:2))+hex2dec(dataHexCurr(3:4));81             dataHex=strcat(dataHex,dataHexCurr);82         end83     end84    checkSum=checkSum+dataRow*dataBits/byteBits;85     checkSum=(dec2hex(bitand(256-mod(checkSum,256),255),2)); 86 %     disp([num2str(i),‘--‘,dataHex,‘--‘,checkSum])87     fprintf(fh,[‘:‘,dec2hex(dataRow*dataBits/byteBits,2),addr,‘00‘,dataHex,checkSum,13,10]);%产生HEX码(end-1:end)88 end89 90 fprintf(fh,‘:00000001FF‘);    91 fclose(fh);

 1 function [ hex ] = num2binary16he( number ) 2 %The IEEE 754 standard specifies a binary16 as having the following format: 3  4 %Sign bit: 1 bit 5 %Exponent width: 5 bits 6 %Significand precision: 11 bits (10 explicitly stored) 7 %S EEEEE MMMMMMMMMM 8 %INPUT: number is a random precision number 9 10 %OUTPUT : var binary is a 2‘s string of the binary1611 %         var decimail is the value of the number in decimal12 13 %Author :Yang Li .14 %Email: yangli0534@gmail.com15 if real(number) >= 2^14  16     error(‘beyond the maximum :-2^14--+2^24‘);17 end18 19 S=number<0 ;20 E=0; 21 M=abs(number);22 while((E>-15 && E<15)&&( M>=2 || M<1 ))23     if(M>=2)24      E=E+1;25      M=M/2;26     else27         E=E-1;28         M=M*2;29     end    30 end31 if ((E==-15 || E==15)&& M>=2 || M<1)32     M=0;33 else34     M=round((M-1)*2^10) ; 35 end36 37 38   number1=(-1)^S*(2^ E   )*(1+M/2^10);39 % binary=strcat(num2str(S),num2str(E),num2str(M)) 40 E =E+15;41 binary=strcat(num2str(S),dec2bin(E,5), dec2bin(M,10)) ;42 43 44 sReal=(str2double(binary(1)));45 eReal =-15; 46  for i=2:647     eReal=eReal+str2double(binary(i))*2^(6-i);48  end    49 %  eReal=eReal*(-1)^str2double(binary(2));50  mReal = 0; 51 for i=7:1652     mReal=mReal+str2double(binary(i))*2^(16-i);53 end 54  55 numberReal=(-1)^sReal*2^eReal*(1+mReal/2^10);56 err=num2str(abs(number-numberReal));57 decimal=numberReal;58 % disp([‘the origin data is : ‘,num2str(number)]);59 % disp([‘the float format is : ‘,binary]); 60 % disp([‘so ,there is a error :‘,num2str(abs(number-numberReal))]);61 62 num=0;63 for i=1:1664     num=num+str2double(binary(i))*2^(16-i);65 end66 hex=dec2hex(num,4);67 end