; CHECK 8/17/85-12/21, A. B. Langdon›; Determine length, CRC and checksum of file.›; Also number of lines, for text file.›;SET $491=$4000 SET 14=$491^›BYTE JMP=[$4C]: CARD Entry›;INCLUDE "D:SYSLIB.ACT"›;INCLUDE "D:SYSIO.ACT"›; Using channel 1, Close caused "system error" with DOS 2.1 but not DOS XL.›; ACS bbs has a block read (BLKIO.ACT) in machine code segments that is›; smaller and has a general purpose call to CIO. Here, I'll leave mine›; as it illustrates use of the language and is just as fast.›; First global ARRAY, other than BYTE ARRAY of length less than 257,›; is placed AFTER rest of program (undocumented?).›BYTE ARRAY buffer(257)   ; locate the buffer.›CARD FLen, ; File length up to 64K›     i, CSum, NLines›BYTE OpOK, CSum0=CSum, CSum1=CSum+1, text›BYTE CIO_status ; global for CIO return value (per ACS convention)›INCLUDE "CRC.ACT"›CARD FUNC GetAD(BYTE chan CARD addr, len) ; Block read›  TYPE IOCB=[BYTE hid,dno,com,sta›             CARD badr,put,blen›             BYTE aux1,aux2,aux3,aux4,aux5,aux6]›  IOCB POINTER ic›  BYTE chan16›  BYTE POINTER b›  chan16 = (chan&$07) LSH 4›  ic = $340+chan16›  ic.com = 7 ; read›  ic.blen = len›  ic.badr = addr›  [$AE chan16 $20 $E456 $8C CIO_status] ; LDX chan, JSR CIO; STY CIO_status›  FLen ==+ ic.blen  ; this to RETURN is special to this application.›  IF CIO_status = $88 THEN›    EOF(chan)=1›    IF (FLen&$FF) = 0 THEN ; likely last sector of›      b = addr+ic.blen-1      ; a DOS 4 file.›      WHILE b^ = 0 DO›        b ==- 1›        ic.blen ==- 1›        FLen == -1›      OD›    FI›  FI›  b = addr›  FOR i = 1 TO ic.blen DO›    IF b^ = $9B THEN NLines ==+ 1 FI›    CSum0 ==+ b^›    CSum1 ==+ CSum0›    updCRC(b^)›    b ==+ 1›  OD›RETURN (ic.blen)›CARD FUNC GetCD(BYTE chan) ; Read a word›  CARD c›  GetAD(chan,@c,2)›RETURN (c)›PROC FixFlSp(BYTE ARRAY FileSpec)›  IF FileSpec(2)<>': AND FileSpec(3)<>': THEN ; prefix "D:" to file name›    FileSpec^==+2›    i=FileSpec^›    WHILE i>2 DO›      FileSpec(i)=FileSpec(i-2)›      i==-1›    OD›    FileSpec(1)='D  FileSpec(2)=':›  FI›; Could also convert to upper case: if >$60 then subtract $20.›RETURN›PROC SysErr(BYTE errno)›PROC MyError(BYTE errno)›  IF errno=$80 THEN Error=SysErr Error(errno) FI ; break quits›  PrintF("error %I. Try again%E",errno)›  OpOK=0›RETURN›PROC End=*() [$68$AA$68$CD$2E8$90$5$CD$2E6$90$F3 $48$8A$48$60]›; entry: PLA; TAX; PLA; CMP MEMLO+1; BCC lab; CMP MEMTOP+1; BCC entry;›; lab: PHA; TXA; PHA; RTS›; Trace back thru RTS's and return to cartridge or DOS.›; From ACS bulletin board.›PROC CHECK()›  CHAR ARRAY FileSpec(20)›  BYTE b, SHFLOK=$2BE›  CARD fwa, lwa, BufLen, MEMTOP=$2E5, MEMLO=$2E7›  BufLen=MEMTOP-$80-buffer›  SysErr=Error›  DO›    Print("File Spec=")›    SHFLOK=$40 ; upper case›    InputS(FileSpec)›    IF FileSpec^=0 THEN END() FI›    FixFlSp(FileSpec)›    Close(2)›    OpOK=1 Error=MyError Open(2,FileSpec,4,0)›  UNTIL OpOK OD›  Error=SysErr›  FLen=0 CSum=0 CRC=0 text=1 NLines=0›; With DOS 4, this artifice ensures ›; that each GetAD reads one byte into›; next sector, to anticipate EOF.›  BufLen ==& $FF00›  GetAD(2,buffer,1)›  IF buffer(0) = $FF THEN text=0 FI›  WHILE EOF(2) = 0 DO›    GetAD(2,buffer,BufLen)›  OD›  updCRC(0) updCRC(0)›  PrintF("End of file. %H bytes%E",FLen)›  PrintF(" checksum=%H, CRC=%H%E",CSum,CRC)›  IF text THEN›    PrintF("%I lines%E",NLines)›  FI›  Close(2)›RETURN›PROC Main()›  device=0 ; in case MAC/65 has been here›  SetupCRC()›  DO›    CHECK()›    PrintE(" (RETURN to end)")›  OD›RETURN›SET Entry=Main›---------------------------------------------------------------------------›MODULE; CRC.ACT    12/21/85 A. B. Langdon›;  Before use, do SetupCRC().›;  For each data set, first set global CRC=0.›;  After calling updCRC(data) with all›; data bytes, do updCRC(0) twice.›;  If CRCx is the CRC of a byte string,›; then the CRC of that string, followed by›; the hi and lo bytes of CRCx, is zero.›CARD CRC: BYTE CRCl=CRC, CRCh=CRC+1›CARD ARRAY CRCtable(256)›;PROC updCRCa(BYTE b) ; Action version›;  From C code by D. Krantz,›; Dr. Dobb's Journal, June 1985.›; Takes 99 jiffies for 2000 bytes.›; BYTE i›; CARD flag›; FOR i=0 TO 7 DO›;   flag = CRC&$8000›;   CRC ==LSH 1›;   IF b&$80 THEN CRC ==% 1 FI›;   IF flag THEN CRC ==XOR $1021 FI›;   b ==LSH 1›; OD›;RETURN›PROC updCRC(BYTE b)›; Adaptation to this CRC of the algorithm›; by W.D.Schwaderer, PC Tech Journal, 4/85.›; Takes 14 jiffies for 2000 bytes.›  CARD tem›  BYTE teml=tem, temh=tem+1›  teml = b›  temh = CRCl›  CRC = tem XOR CRCtable(CRCh)›RETURN›PROC updCRCx=*(BYTE b)›; Machine language for Dr. Dobb's routine.›; Takes 35 jiffies for 2000 bytes.›  [$85$A0]            ; STA $A0›  [$A2$8]             ; loop over 8 bits›  [$26$A0]            ; 3 byte shift of data›  [$2E CRC $2E CRC+1]          ; and CRC›  [$90$10 $AD CRC $49$21 $8D CRC] ; if carry, then XOR›  [$AD CRC+1 $49$10 $8D CRC+1] ; poly bits›  [$CA $D0$E3]        ; loop›RETURN›PROC SetupCRC()›  FOR i=0 TO $FF DO ; set up CRC table›    CRCl=0 CRCh=i›    updCRCx(0)›    CRCtable(i)=CRC›  OD                ; <0.1 sec.›RETURN›MODULE; end CRC›