【精品】vhdl双语教学第6章（可编辑.ppt

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1、VHDL双语教学第6章2023/3/14【可编辑】AgendaOther Features in VHDLGenerateAssertFunctionOverloadingFILEIOGenerate Example(1)ram32:ram_0:static_ram portmap(cs_b,we_b,oe_b,abus(7downto0),dbus(7downto0);ram_1:static_ram portmap(cs_b,we_b,oe_b,abus(7downto0),dbus(15downto8);ram_2:static_ram portmap(cs_b,we_b,oe_b,ab

2、us(7downto0),dbus(23downto16);ram_3:static_ram portmap(cs_b,we_b,oe_b,abus(7downto0),dbus(31downto24);endgenerateram32;RAM0RAM1RAM2RAM38-bitBus8-bitBus8-bitBus8-bitBus32-bitBus8-bit addr8-bit addr8-bit addr8-bit addrGenerate Example(2)ram32:foriin3downto0generateram:static_ram portmap(cs_b,we_b,oe_b

3、,abus(7downto0),dbus(8*i+7downto8*i);endgenerateram32;RAM0RAM1RAM2RAM38-bitBus8-bitBus8-bitBus8-bitBus32-bitBus8-bit addr8-bit addr8-bit addr8-bit addrGenerateLabel:forParameterNameinRangegenerateConcurrentStatements.endgenerateLabel;Label:ifConditiongenerateConcurrentStatements.endgenerateLabel;Age

4、ndaGenerateAssertFunctionOverloadingFILEIOAssertDefinitionLabel:assertConditionreport StringExpressionseverity Expression;Notel lThe message is written when the Condition isThe message is written when the Condition is False!lThedefaultstringforreportreportclauseis“Assertionviolation”lThedefaultstrin

5、gforseverity severity clauseis“ERROR”Concurrent Assertions&Concurrent Procedure CallsLabel:assertconditionreporterror_stringseverityseverity_value;Label:processbeginassertconditionreporterror_stringseverityseverity_value;wait sensitivity_clause;end processLabel;concurrent assertionsconcurrent proced

6、ure callsAssert Example(1)assertnot(Reset=0 and Set=0)reportR-S conflictseverityFailure;Assert Example(2)Severity_leveltypeseverity_levelis(note,warning,error,failure);(Instandard.vhd)AgendaGenerateAssertFunction OverloadingFILEIOFunction OverloadingVHDLallowstwosubprogramstohavethesame name,provide

7、dthenumber or base types of parameters differsFunction Overloading(Example 1)functionFoo(value:bit)returnboolean;functionFoo(value:std_logic)returnboolean;Function Overloading(Example 2)function+(arg1,arg2:STD_LOGIC_VECTOR)returnSTD_LOGIC_VECTOR;function+(L,R:UNSIGNED)returnUNSIGNED;function+(L,R:SI

8、GNED)returnSIGNED;Function Overloading(Example 3)FUNCTION+(arg1,arg2:STD_LOGIC_VECTOR)RETURN STD_LOGIC_VECTOR ISCONSTANTml:INTEGER:=maximum(arg1length,arg2length);VARIABLElt:STD_LOGIC_VECTOR(1TOml);VARIABLErt:STD_LOGIC_VECTOR(1TOml);VARIABLEres:STD_LOGIC_VECTOR(1TOml);VARIABLEcarry:STD_LOGIC:=0;VARI

9、ABLEa,b,s1:STD_LOGIC;-Unsignedarithmeticadditionoftwovectors.MSBisLeft.ATTRIBUTEsynthesis_returnOFres:VARIABLEISADD;BEGINlt:=zxt(arg1,ml);rt:=zxt(arg2,ml);FORiINresreverse_rangeLOOPa:=lt(i);b:=rt(i);s1:=a+b;res(i):=s1+carry;carry:=(aANDb)OR(s1ANDcarry);ENDLOOP;RETURNres;END;FUNCTION+(arg1,arg2:UNSIG

10、NED)RETURN UNSIGNED ISCONSTANTml:INTEGER:=maximum(arg1length,arg2length);VARIABLElt:UNSIGNED(1TOml);VARIABLErt:UNSIGNED(1TOml);VARIABLEres:UNSIGNED(1TOml);VARIABLEcarry:STD_LOGIC:=0;VARIABLEa,b,s1:STD_LOGIC;-Unsignedarithmeticadditionoftwovectors.MSBisLeft.ATTRIBUTEsynthesis_returnOFres:VARIABLEISAD

11、D;BEGINlt:=zxt(arg1,ml);rt:=zxt(arg2,ml);FORiINresreverse_rangeLOOPa:=lt(i);b:=rt(i);s1:=a+b;res(i):=s1+carry;carry:=(aANDb)OR(s1ANDcarry);ENDLOOP;RETURNres;END;Function Overloading(Example 4)function+(a,b:byte)returnbyteisbeginreturnint_to_byte(byte_to_int(a)+byte_to_int(b);end+;X1000_0010+X0000_FF

12、D0+(X1000_0010,X0000_FFD0)AgendaGenerateAssertFunctionOverloadingFILE IOl lText FileText FilelBinaryFileRead/Write Text File12123122341Awfe011100010-Disk File1001011011Line variableReadLine()Read()Data Object12123122341Awfe011100010-Disk File1001011011Line variableWriteLine()Write()Data ObjectRead F

13、rom Text FileWrite To Text FileRead/Write Text File StepsStep1 Defineuserdataobject,DataObjStep2 DefineLineobject,LineObjvariable LineObj:line;Step2 DefineTextFileobject,FileObj file FileObject:text is in FileName;file FileObject:text is out FileName;Step4 Read/WriteDatalReadreadLine(FileObj,LineObj

14、);read(LineObj,DataObj);lWriteWrite(LineObj,DataObj);WriteLine(FileObj,LineObj);Read/Write Text File(Example)libraryieee;useieee.std_logic_1164.all;usestd.textio.all;entitytext_file_readisendtext_file_read;architecturetext_file_read_aoftext_file_readisbeginprocessvariablebv:bit_vector(3downto0);vari

15、able ln_in:line;variable ln_out:line;file file_in:text is in text1.dat;file file_out:text is out text2.dat;beginloopexitwhenendfile(file_in);readline(file_in,ln_in);read(ln_in,bv);write(ln_out,bv);writeline(file_out,ln_out);endloop;wait;endprocess;endtext_file_read_a;11111010text1.dat11111010text2.d

16、atWrite Text File(Example 1)libraryieee;useieee.std_logic_1164.all;usestd.textio.all;entitytext_file_writeisendtext_file_write;architecturetext_file_write_aoftext_file_writeisbeginprocessvariable ln:line;variable bv:bit_vector(3 downto 0);file out_file:text is out text1.dat;begin bv:=1111;write(ln,b

17、v);writeline(out_file,ln);bv:=1010;write(ln,bv);writeline(out_file,ln);wait;endprocess;endtext_file_write_a;11111010text1.datWrite Text File(Example 2)entityWrite_FileisendentityWrite_File;architecturearch_Write_FileofWrite_FileissignalA,B,C:Bit_vector(3downto0);beginA=1100;B=0110;C=0101;Monitor:pro

18、cessuseSTD.TEXTIO.all;fileF:TEXTisoutc:test.txt;-VHDL87variableL:LINE;beginWRITE(L,NOW,Left,10);WRITE(L,A,Right,5);WRITE(L,B,Right,5);WRITE(L,C,Right,5);WRITELINE(F,L);wait for 0 ns;WRITE(L,NOW,Left,10);WRITE(L,A,Right,5);WRITE(L,B,Right,5);WRITE(L,C,Right,5);WRITELINE(F,L);wait for 1 ns;WRITE(L,NOW

19、,Left,10);WRITE(L,A,Right,5);WRITE(L,B,Right,5);WRITE(L,C,Right,5);WRITELINE(F,L);wait;endprocess;endarchitecturearch_Write_File;0 ns 0000 0000 00000 ns 1100 0110 01011 ns 1100 0110 0101 10 5 5 5AgendaGenerateAssertFunctionOverloadingFILE IOlTextFilel lBinary FileBinary FileRead/Write Binary FileSte

20、p1 DefineFileFormat(Storedatatype)DataTypeStep2 Defineuserdataobject,DataObjStep3 DefineFileobject,FileObjfile FileObject:DataType is in FileName;file FileObject:DataType is out FileName;Step4 Definedatalengthvariable,LengthStep5 Read/WriteDataread(FileObj,DataType,Length);write(FileObj,DataObject);

21、Write Binary Filelibraryieee;useieee.std_logic_1164.all;usestd.textio.all;entityfile_writeisendfile_write;architecturefile_write_aoffile_writeistypebit_vecisfileofbit_vector;file out_file:bit_vec is out F1.dat;beginprocessvariablev:bit_vector(3downto0);beginv:=1101;write(out_file,v);waitfor100ms;v:=

22、0001;write(out_file,v);waitfor100ms;v:=1111;write(out_file,v);waitfor100ms;wait;endprocess;endfile_write_a;Read/Write Binary Filearchitecturefile_read_aoffile_readistypebit_vecisfileofbit_vector;filein_file:bit_vecisinF1.dat;fileout_file:bit_vecisoutF2.dat;beginprocessvariablev:bit_vector(3downto0);

23、variablelen:natural:=1;beginloopexitwhenendfile(in_file);read(in_file,v,len);write(out_file,v);waitfor100ms;endloop;wait;endprocess;endfile_read_a;libraryieee;useieee.std_logic_1164.all;usestd.textio.all;entityfile_readisendfile_read;Definitions For Text File(1)packageTEXTIOis-Typedefinitionsfortext

24、I/O:typeLINEisaccessSTRING;-ALINEisapointertoaSTRINGvalue.typeTEXTisfileofSTRING;-Afileofvariable-lengthASCIIrecords.typeSIDEis(RIGHT,LEFT);-Forjustifyingoutputdatawithinfields.subtypeWIDTHisNATURAL;-Forspecifyingwidthsofoutputfields.-Standardtextfiles:fileINPUT:TEXTopenREAD_MODEisSTD_INPUT;fileOUTP

25、UT:TEXTopenWRITE_MODEisSTD_OUTPUT;-Inputroutinesforstandardtypes:procedureREADLINE(fileF:TEXT;L:outLINE);procedureREAD(L:inoutLINE;VALUE:outBIT;GOOD:outBOOLEAN);procedureREAD(L:inoutLINE;VALUE:outBIT);procedureREAD(L:inoutLINE;VALUE:outBIT_VECTOR;GOOD:outBOOLEAN);procedureREAD(L:inoutLINE;VALUE:outB

26、IT_VECTOR);procedureREAD(L:inoutLINE;VALUE:outBOOLEAN;GOOD:outBOOLEAN);procedureREAD(L:inoutLINE;VALUE:outBOOLEAN);procedureREAD(L:inoutLINE;VALUE:outCHARACTER;GOOD:outBOOLEAN);Definitions For Text File(2)procedureREAD(L:inoutLINE;VALUE:outCHARACTER);procedureREAD(L:inoutLINE;VALUE:outINTEGER;GOOD:o

27、utBOOLEAN);procedureREAD(L:inoutLINE;VALUE:outINTEGER);procedureREAD(L:inoutLINE;VALUE:outREAL;GOOD:outBOOLEAN);procedureREAD(L:inoutLINE;VALUE:outREAL);procedureREAD(L:inoutLINE;VALUE:outSTRING;GOOD:outBOOLEAN);procedureREAD(L:inoutLINE;VALUE:outSTRING);procedureREAD(L:inoutLINE;VALUE:outTIME;GOOD:

28、outBOOLEAN);procedureREAD(L:inoutLINE;VALUE:outTIME);-Outputroutinesforstandardtypes:procedureWRITELINE(fileF:TEXT;L:inoutLINE);procedureWRITE(L:inoutLINE;VALUE:inBIT;JUSTIFIED:inSIDE:=RIGHT;FIELD:inWIDTH:=0);procedureWRITE(L:inoutLINE;VALUE:inBIT_VECTOR;JUSTIFIED:inSIDE:=RIGHT;FIELD:inWIDTH:=0);pro

29、cedureWRITE(L:inoutLINE;VALUE:inBOOLEAN;JUSTIFIED:inSIDE:=RIGHT;FIELD:inWIDTH:=0);procedureWRITE(L:inoutLINE;VALUE:inCHARACTER;JUSTIFIED:inSIDE:=RIGHT;FIELD:inWIDTH:=0);Definitions For Text File(3)procedureWRITE(L:inoutLINE;VALUE:inINTEGER;JUSTIFIED:inSIDE:=RIGHT;FIELD:inWIDTH:=0);procedureWRITE(L:i

30、noutLINE;VALUE:inREAL;JUSTIFIED:inSIDE:=RIGHT;FIELD:inWIDTH:=0;DIGITS:inNATURAL:=0);procedureWRITE(L:inoutLINE;VALUE:inSTRING;JUSTIFIED:inSIDE:=RIGHT;FIELD:inWIDTH:=0);procedureWRITE(L:inoutLINE;VALUE:inTIME;JUSTIFIED:inSIDE:=RIGHT;FIELD:inWIDTH:=0;UNIT:inTIME:=ns);-Filepositionpredicate:-functionENDFILE(fileF:TEXT)returnBOOLEAN;endTEXTIO;