DECLARE SUB CtrMode (addr AS INTEGER, cntr AS ANY, mode AS INTEGER)
DECLARE SUB CtrLoad (addr AS INTEGER, counter AS INTEGER, value AS INTEGER)


'*****************************************************************************
'       This program will set up counter 1 with 100 and 0 with full scale
'       (65535), sending out a pulse when reaching zero.
'******************************************************************************


  ADDRESS% = &H350               ' The Base address of the watchdog board.

  CLS
  PRINT "QuickBasic Sample #1: Use Of Counter/Timer Chip with Watchdog"
  PRINT "This program demonstrates how to program the 82C54 counter/timer"
  PRINT "chip on the Watchdog Timer board.  The Watchdog address should be set"
  PRINT "to 350 hex.  A keystroke will stop the program."
  PRINT "Press any key to start."
  CH$ = INPUT$(1)                       ' Grab keystroke.

  outbyte% = INP(ADDRESS% + 7)           ' Disable counters

  CALL CtrMode(ADDRESS%, 0, 3)           ' set counter 0 to mode 3
  CALL CtrLoad(ADDRESS%, 0, &HFFFF)      ' and load it with full scale

  CALL CtrMode(ADDRESS%, 1, 2)           ' set counter 1 to mode 2
  CALL CtrLoad(ADDRESS%, 1, &H64)        ' and load with 64 hex

  CALL CtrMode(ADDRESS%, 2, 1)           ' set mode on counter 2

  OUT ADDRESS + 7, 0                     ' Disable counters

  FOR Times = 1 TO 1000
    CALL CtrMode(ADDRESS%, 1, 2)
    CALL CtrLoad(ADDRESS%, 1, &HFFFF)
    PRINT "Updating counter 1.  Loop number : "; Times
    LOCATE 6, 1
  NEXT Times

  PRINT
  PRINT "Waiting for timeout . . ."

key$ = ""

WHILE ((INP(ADDRESS% + 4) AND 128) = 128) AND (key$ = "")    ' Check first bit for near timeout
   key$ = INKEY$
WEND

PRINT
IF (key$ = "") THEN PRINT "Watchdog timed out successfully." ELSE
   PRINT "Timeout aborted!"

END

SUB CtrLoad (addr AS INTEGER, counter AS INTEGER, value AS INTEGER)
    OUT addr + counter, value MOD 256
    OUT addr + counter, value / 256
END SUB

SUB CtrMode (addr AS INTEGER, cntr AS INTEGER, mode AS INTEGER)
    ctrl% = (cntr * 64) OR &H30 OR (mode * 2)
    OUT addr + 3, ctrl%
END SUB