;This program will change the density of any PERCOM compatible drive from›;single to double density and vice versa.  It also displays the values›;in the drive option table before and after the change.›;Note that by changing the CHANGE_DENSITY() procedure you could configure›;the disk controller to handle a double sided or 96TPI (quad density)›;drive, assuming your controller can handle these drive types.›;(The PERCOM RFD-1 and ATR8000 can, the TRAK, INDUS, etc. can't)›› ›DEFINE RDOCMD="$4E", WROCMD="$4F",›       TIMEOUT="$0F", SIOUT="$80",›       SIOIN="$40", BUSSID="'1"››››BYTE DCB=$0300, DDEVIC=$0300, DUNIT=$0301,›     DCOMND=$0302, DSTATS=$0303, DTIMLO=$0306,›     DRIVENUMBER››CARD DBUF=$0304, DBYTE=$0308, DAUX12=$030A,›     SECTOR_SIZE,BUF256›BYTE POINTER PTR››BYTE ARRAY BUFFER(12) ›››PROC  SIO=$E459()   ;define location of serial bus handler››PROC FIRE_IO(BYTE TIME, COMND, STATS CARD BUF, BYTES)››;this routine sets up the Device Control Block›;and calls the SIO routine in the OS.››      DDEVIC=BUSSID›      DUNIT=DRIVENUMBER›      DCOMND=COMND›      DTIMLO=TIME›      DSTATS=STATS›      DBUF=BUF›      DBYTE=BYTES›      SIO()›RETURN›››PROC OPTION_TABLE_ERROR()››;dummy error handling routine, put your own here I got lazy››RETURN››PROC OPTION_TABLE(BYTE CMND)›       BYTE STATSD             ;STATSD controls the direction of data ›                               ;transfer›         IF CMND=RDOCMD THEN   ;read option table›             STATSD=SIOIN      ;set for data in›         ELSEIF CMND=WROCMD THEN ;write option table›             STATSD=SIOUT      ;set for data out›         ELSE›             OPTION_TABLE_ERROR()›             RETURN›         FI›         FIRE_IO(TIMEOUT,CMND,STATSD,BUF256,$0C)›         IF DSTATS#1 THEN›             OPTION_TABLE_ERROR()›         FI        ›RETURN››PROC TEST_OPTION_TABLE()››;this routine reads the option table and displays the values››   BYTE BUFBYTE ›   CARD BUFCARD›      PTR=BUFFER›      BUF256=PTR›      OPTION_TABLE(RDOCMD)›       PRINT("TRACKS    ")›      BUFBYTE=PTR^›      PRINTBE(BUFBYTE)›       PRINT("STEP RATE ")›       PTR==+1›       BUFBYTE=PTR^›       PRINTBE(BUFBYTE)›       PRINT("SEC/TRACK ")›       PTR==+1›       BUFCARD=256*PTR^›       PTR==+1›       BUFCARD==+PTR^›       PRINTCE(BUFCARD)›       PRINT("SIDES     ")›       PTR==+1›       BUFBYTE=PTR^›       PRINTBE(BUFBYTE)›       PRINT("DENSITY   ")›       PTR==+1›       BUFBYTE=PTR^›       PRINTBE(BUFBYTE)›       PRINT("SEC SIZE  ")›       PTR==+1›       BUFCARD=256*PTR^›       PTR==+1›       BUFCARD==+PTR^›       PRINTCE(BUFCARD)›       PRINT("PRESENT   ")›       PTR==+1›       BUFBYTE=PTR^›       PRINTBE(BUFBYTE)›RETURN››PROC CHANGE_DENSITY(BYTE NEW_DENSITY)››       PTR=BUFFER›       BUF256=PTR›       OPTION_TABLE(RDOCMD)    ;read option table›       IF NEW_DENSITY=1 THEN   ;sets single density›        PTR==+5›        PTR^=0                 ;single/double flag›        PTR==+1›        PTR^=0                 ;high byte of sector size›        PTR==+1›        PTR^=$80               ;low byte of sector size›        OPTION_TABLE(WROCMD)   ;write new info›       ELSEIF NEW_DENSITY=2 THEN  ;sets double density›        PTR==+5›        PTR^=4                 ;density flag›        PTR==+1›        PTR^=1                 ;high byte of sector size›        PTR==+1›        PTR^=0                 ;low byte of sector size›        OPTION_TABLE(WROCMD)›       FI›RETURN›››PROC MAIN()››       BYTE CHANGE_TYPE››       PRINTE("ENTER THE DRIVE NUMBER YOU WISH TO")›       PRINTE("CHANGE THE DENSITY OF")›       DRIVENUMBER=INPUTB()››       TEST_OPTION_TABLE()››       PRINTE("ENTER '1' IF YOU WANT TO MAKE DRIVE")›       PRINT("NUMBER ")›       PRINTB(DRIVENUMBER)›       PRINTE(" SINGLE DENSITY")›       PRINTE("ENTER '2' IF YOU WANT TO MAKE DRIVE")›       PRINT("NUMBER ")›       PRINTB(DRIVENUMBER)›       PRINTE(" DOUBLE DENSITY")›       CHANGE_TYPE=INPUTB()›   ›       CHANGE_DENSITY(CHANGE_TYPE)›     ›       TEST_OPTION_TABLE()›RETURN››