asterisk 5c
Character Hex Equivalent 0 F0 1 F1 2 F2 3 F3 4 F4 5 F5 6 F6 7 F7 8 F8 9 F9 blank 40 comma 6b decimal point 4b asterisk 5c
EBCDIC Encoding
Character Instructions - MVC Move CharactersSS1Op2 – source fieldLength – associated with operand 1 only!Default Length is length of operand 1Fields may overlapMax 256 bytes are moved
Character Instructions - MVC X DC Cl5’ABC’Y DC CL7’1234567’ MVC X,Y MVC Y,X MVC X,=C’XYZ’ dangerous, why?
Blanking Out a Line BLANK DC C’ ’ BUFFER DS CL133 MVC BUFFER,BLANK MVI BUFFER,C’ ’ MVC BUFFER+1(L’BUFFER-1),BUFFER MVC BUFFER,=CL133’ ’
Compare Logical CharactersSS1Sets the condition code to indicate how Op1 compares to Op2Length – associated with operand 1 only!Default Length is length of operand 1Bytes compared using EBCDIC encodingBytes compared left to rightMax 256 bytes are comparedTest with BE, BL, BH, BNE, BNL, BNH
Character Instructions - CLC X DC Cl5’ABC’Y DC CL7’1234567Z DC C’ABCD’ CLC X,Y CLC Y,X CLC X(2),Z explicit length CLC Z,X BL THERE
Compare Logical ImmediateSIConstant resides inside the instructionSets the condition code to indicate how Op1 compares to Op2Implicit length of 1!Byte compared using EBCDIC encodingTest with BE, BL, BH, BNE, BNL, BNH
Character Instructions - CLI X DC Cl5’ABC’Y DC CL7’1234567Z DC C’ABCD’ CLI X,C’A’ Character CLI Y,C’A CLI X,X’40’ Hex CLI Z,64 Decimal CLI Z,B’11110001’ Binary BL THERE
Character Instructions - MVI Move ImmediateSIConstant resides inside the instructionImplicit length of 1!
Character Instructions - MVI X DC Cl5’ABC’Y DC CL7’1234567Z DC C’ABCD’ MVI X,C’F’ Character MVI Y,C’A’ MVI X,X’40’ Hex MVI Z,64 Decimal MVI Z,B’11110001’ Binary
Defining an Output File *********************************************************** * **********************************************************FILEOUT DCB DSORG=PS, X MACRF=(PM), X DDNAME=FILEOUT, X RECFM=FBM, X LRECL=80
Defining an Input File *********************************************************** * INPUT FILE - DATA CONTROL BLOCK * **********************************************************FILEIN DCB DSORG=PS, X MACRF=(GM), X DDNAME=FILEIN, X RECFM=FB, X EODAD=FINAL X LRECL=80
DCB (Data Control Block) Parms MACRF=(GM)- Macro format – controls the type of macros that are used for file
- GM – input file, move mode
- GL – input file, locate mode
- PM – output file, move mode
- PL – output file, locate mode
- We will start with GM and PM since these are the easiest, but GL and PL are the most efficient for files with large record sizes and many records
DDNAME= name
DCB (Data Control Block) Parms DSORG=PS - A Physical sequential file organization
Dostları ilə paylaş:
|
