matlab生成HEX文件

HEX文件格式不赘述，写里直接放上代码。请批评改正。

 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 [email protected]
 5 % data:2015.01.27
 6
 7 clear all;
 8 close all;
 9 clc;
10
11 %% fixed point or binary16 float point
12 fixed=1;
13 %% generate a signal waveform
14 %
15 T=10;%time length
16 fs=1e3;%sample rate
17 N=10000;
18 Period=N/fs/10;
19 f=1/Period;
20 t=linspace(0,(N-1)/fs,N);
21
22 %data=1:2^5-1;
23 data= sin(2*pi*f*t) +(rand(1,N)-0.5)/10;
24 % data=mod(50000*t,1000);
25 % plot(t,data)
26 dataBits=16;
27 byteBits=8;
28
29 %% convert into 16 bits fixed point number
30 if fixed == 1
31     maximum=max(abs(data));%maximum of absolute signal
32     scale=(2^15-1)/maximum;%scale
33     data=round(data*scale);
34     for i=1:1:length(data)
35         if data(i) <0
36             data(i) =2^16-abs(data(i)) ;
37         end
38     end
39 end
40 %% write
41 fh=fopen(‘data.hex‘,‘w‘);%open a new file (file path, file name)
42 bytesEveryRow=16;%write 16 bytes every row
43 dataEveryRow=bytesEveryRow/(dataBits/byteBits);%number of data every row
44 lengthData=length(data);%length of signal data
45 rowLengths=ceil(lengthData/dataEveryRow);%number of rows of the file to be written
46
47 for i=1:rowLengths % write a row each time
48     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     end
55     checkSum=0;
56     addr=dec2hex(mod((i-1)*16,hex2dec(‘10000‘)),4);%the start address of this row
57     checkSum=hex2dec(addr(1:2))+hex2dec(addr(3:4));
58     if i*dataEveryRow <lengthData %  numbers of data to be written greater than dataEveryRow
59         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 point
64              else
65                 dataHexCurr=num2binary16hex(data(j));%number format: 16bits floatIEEE 754 half precison float point standard,result is a hex format
66              end
67             checkSum=checkSum+hex2dec(dataHexCurr(1:2))+hex2dec(dataHexCurr(3:4));
68             dataHex=strcat(dataHex,dataHexCurr);
69         end
70
71     else
72          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 point
77              else
78                 dataHexCurr=num2binary16hex(data(j));%number format: 16bits floatIEEE 754 half precison float point standard,result is a hex format
79              end
80             checkSum=checkSum+hex2dec(dataHexCurr(1:2))+hex2dec(dataHexCurr(3:4));
81             dataHex=strcat(dataHex,dataHexCurr);
82         end
83     end
84    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 end
89
90 fprintf(fh,‘:00000001FF‘);
91 fclose(fh);

代码中有定点浮点两种，其中浮点格式为IEEE754标准中的half-precision-floating point, 16bit, 1bit 浮号位，5bit指数位，10小数位，代码如下：

 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 binary16
11 %         var decimail is the value of the number in decimal
12
13 %Author :Yang Li .
14 %Email: [email protected]
15 if real(number) >= 2^14
16     error(‘beyond the maximum :-2^14--+2^24‘);
17 end
18
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     else
27         E=E-1;
28         M=M*2;
29     end
30 end
31 if ((E==-15 || E==15)&& M>=2 || M<1)
32     M=0;
33 else
34     M=round((M-1)*2^10) ;
35 end
36
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=2:6
47     eReal=eReal+str2double(binary(i))*2^(6-i);
48  end
49 %  eReal=eReal*(-1)^str2double(binary(2));
50  mReal = 0;
51 for i=7:16
52     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=1:16
64     num=num+str2double(binary(i))*2^(16-i);
65 end
66 hex=dec2hex(num,4);
67 end