DECLARE FUNCTION AskForBaseAddress! (OldOne AS INTEGER)
'***************************************************************************
'* This sample program will sequentially turn on all bits of port 0 of the *
'* IOD64 and then sequentially turn them off.  Each time it sets a new bit,*
'* both port 0 and port 1 are read and the data displayed.  This           *
'* demonstrates how to read and write to a port, and to use the read back  *
'* function of the board.                                                  *
'***************************************************************************
'
DIM CURRENT%(3)
'
'print the string display
'
CLS
PRINT "                       SAMPLE 1.BAS : IOD-64S"
PRINT
PRINT "This sample program will sequentially turn on all bits of port 0 of the"
PRINT "IOD64 and then sequentially turn them off.  Each time it sets a new bit,"
PRINT "both port 0 and port 1 are read and the data displayed.  This"
PRINT "demonstrates how to read and write to a port, and to use the read back"
PRINT "function of the board."
LOCATE 10, 1
Address% = AskForBaseAddress!(&H300)
CLS
PRINT
PRINT
PRINT "Board Configuration"
PRINT
PRINT " -- Base Address is "; HEX$(Address%); " hex."
PRINT " -- All remaining jumper settings are irrelevant."
PRINT : PRINT : PRINT
PRINT "Press a key to continue."
ch$ = INPUT$(1)
CLS
LOCATE 1, 10
PRINT " I O D 6 4  C A R D  S A M P L E  P R O G R A M "
LOCATE 6, 17
PRINT " PORT 0 OUTPUT    PORT 0 INPUT      PORT 1 INPUT"
LOCATE 7, 17
PRINT " -------------    ------------      ------------ "
LOCATE 10, 28
PRINT " PRESS F1 TO EXIT PROGRAM "
'
'main control loop
'
CURRENT(0) = 0
SHIFTLEFT% = 1
OUT Address% + 8, &H1
ON KEY(1) GOSUB QUIT
KEY(1) ON
'
'this loop will repeat endlessly until F1 is pressed
'
CONT:
OUT Address%, CURRENT%(0)    'write value to port 0
CURRENT%(1) = INP(Address%)  'read back back what we wrote to port 0
CURRENT%(2) = INP(Address% + 1) 'read the data on port 1
'
'write the data to the screen
'
X = 20                'starting x coordinate to write data to screen
FOR INDEX = 0 TO 2    'for each array member
   VALUE% = CURRENT%(INDEX)
   FOR INDEX1 = 0 TO 7 'for each bit in array member */
       LOCATE 8, X
       VALUE1% = VALUE% MOD 2
       IF VALUE1% = 1 THEN PRINT "1" ELSE PRINT "0"
       VALUE% = (VALUE% - 1) / 2     ' roll next display bit
       X = X + 1
   NEXT INDEX1
   X = X + 10
NEXT INDEX
'
'compute value to turn on/off next bit in line
'
IF CURRENT%(0) = 0 THEN SHIFTLEFT = 1
IF CURRENT%(0) = 255 THEN SHIFTLEFT = 0
IF SHIFTLEFT = 1 THEN CURRENT%(0) = CURRENT%(0) * 2 + 1
IF SHIFTLEFT = 0 THEN CURRENT%(0) = (CURRENT%(0) - 1) / 2
FOR X = 0 TO 3500: Y = Y + 1: NEXT X
GOTO CONT

QUIT:
CLS
END

FUNCTION AskForBaseAddress (OldOne AS INTEGER)
   Msg$ = ""
   NewOne% = 0: Success = 0: Dummy% = 0
   AddrInputPosX = 0: AddrInputPosY = 0

   PRINT "Please enter the Base Address (0000-FFFF) for your card (in hex)"
   PRINT "or press ENTER for "; HEX$(OldOne%); "."
   PRINT ">";
   AddrInputPosX = POS(0): AddrInputPosY = CSRLIN
   WHILE Success = 0
     LOCATE AddrInputPosY, AddrInputPosX
     PRINT "                                                                               "
     LOCATE AddrInputPosY, AddrInputPosX
     LINE INPUT Msg$
     NewOne% = VAL("&H0" + LEFT$(Msg$, 4))
     Success = 1
     Dummy% = NewOne%
     IF (Msg$ = "") THEN
        LOCATE AddrInputPosY, AddrInputPosX
        PRINT HEX$(OldOne%)
        Success = 1
        Dummy% = OldOne%
     END IF
  WEND
  AskForBaseAddress = Dummy%
END FUNCTION