'*--------------------------------------------------------------------
'* QSAMPLE3.BAS                            
'*
'* Sample program to demonstrate access to DA12-16 Automatic and
'* Simultaneous Update modes.
'*
'* Last Modified: 22 March 1995.                                  SMG
'*--------------------------------------------------------------------
DECLARE FUNCTION AskForBaseAddress% (OldOne AS INTEGER)
DECLARE FUNCTION Deci% (DS AS STRING)
DECLARE SUB WaitForUser ()

'
'Introductory screen
'
CLS
PRINT ""
PRINT "Sample 3                 DA12-16             "
PRINT ""
PRINT ""
PRINT "Sample demonstrates mode switching and channel programming for the "
PRINT "DA12-16 card."
PRINT
PRINT "DA12-16 configuration for this program: "
PRINT
PRINT " þ All DAC voltage ranges should be set to ñ5v bipolar."

WaitForUser

'
' Prompt user for DA12-16 base address and set global address
' accordingly.
'
BaseAddr% = &H350
BaseAddr% = AskForBaseAddress(BaseAddr%)

'
' Release zero latch
PortVal% = INP(BaseAddr + 15)

'
' Hardware clear??
'
CLS
PRINT ""
PRINT "Do you wish to perform a hardware-reset clear?"
PRINT ""
PRINT "   Answer 'Y' if the card has just been powered up, or 'N' if"
PRINT "   you've already performed this operation since the last reset."
PRINT ""

ResetDAs:
Key$ = INKEY$
Key$ = UCASE$(Key$)
IF Key$ = "Y" THEN
    FOR Channel% = 0 TO 15
        OUT BaseAddr% + (Channel% * 2), &H0
        OUT BaseAddr% + (Channel% * 2) + 1, &H8
        NEXT Channel%
    PortVal% = INP(BaseAddr% + 10)
    CLS
    PRINT ""
    PRINT " All channels have been updated to bipolar zero (800 hex)"
    PRINT "Assuming power-on condition, nothing should have changed."
    PRINT "(Incidentally, any channels set to a uniploar range should"
    PRINT "have simultaneously changed to +2«v outputs."
    WaitForUser

ELSEIF Key$ <> "N" THEN
    GOTO ResetDAs
    END IF


CLS
PRINT ""
PRINT "Press any key to output +2«v on all channels, non-simultaneously."
WaitForUser
'
' Remove from Simultaneous mode (offset 10 would also work)
'
PortVal% = INP(BaseAddr% + 10)

'
' These changes will now take place immediately
'
FOR Channel% = 0 TO 15
    OUT BaseAddr% + (Channel% * 2), &H0
    OUT BaseAddr% + (Channel% * 2) + 1, &HC
    NEXT Channel%

CLS
PRINT ""
PRINT "All channels have been updated to +2«v in Automatic Mode."
WaitForUser

'
'Place in Simultaneous mode
'
PortVal% = INP(BaseAddr% + 0)

'
'The following outputs do not take effect immediately because we are
' now in Simultaneous mode.
'
FOR Channel% = 0 TO 15
    OUT BaseAddr% + (Channel% * 2), &HFF
    OUT BaseAddr% + (Channel% * 2) + 1, &HF
    NEXT Channel%

CLS
PRINT ""
PRINT "All channels have been loaded with FFF hex, but the outputs have"
PRINT "not yet changed. Press any key to initiate simultaneous update"
PRINT "of all channels. Outputs will simultaneously change to +4.9998vdc"
WaitForUser

'
'Simultaneously update all channels
'
PortVal% = INP(BaseAddr% + 8)
CLS
PRINT ""
PRINT "All channels have been simultaneously updated to full scale values."
WaitForUser

FOR Channel% = 1 TO 7 STEP 2
    OUT BaseAddr% + (Channel% * 2), &H0
    OUT BaseAddr% + (Channel% * 2) + 1, &H8
    NEXT Channel%


CLS
PRINT ""
PRINT "Channels 1,3,5,7 have been written to zero but their outputs"
PRINT "have not yet changed. Press any key to update all channels."
WaitForUser

PortVal% = INP(BaseAddr% + 10)
PortVal% = INP(BaseAddr% + 15)

CLS
PRINT ""
PRINT "Channels 1,3,5,7 have been updated"
WaitForUser

PortVal% = INP(BaseAddr% + 10)
PortVal% = INP(BaseAdd% + 15)

ProgCh:
CLS
PRINT "Now you may specify a DAC channel and a DAC count value to set"
PRINT "a desired channel to a specified value"
PRINT "Enter channel value of 99 to quit."
PRINT ""

ChIn:
INPUT "Enter channel (0-15): "; Channel%
IF Channel% = 99 THEN
   GOTO Quit
   END IF
IF (Channel% < 0) OR (Channel% > 15) THEN
    PRINT "Value out of range. Please try again."
    GOTO ChIn
    END IF

GetVoltage:
INPUT "Enter a voltage between -4.997v to 4.997v: ", voltage#
PRINT
IF (voltage# < -4.997) OR (voltage# > 4.997) THEN
   BEEP
   PRINT "Invalid voltage! Please try again."
   GOTO GetVoltage
   END IF

'  Compute the digital output needed for this value and the actual voltage
'  that will be expected, and display the voltage.
counts# = (voltage# + 5!) / .002442
cnts& = counts#
expected# = (cnts& * .002442) - 5!


' Prepare and write values to control word
lowbyte% = cnts& MOD 256
hibyte% = INT(cnts& / 256)

OUT BaseAddr% + (2 * Channel%), lowbyte%
OUT BaseAddr% + (2 * Channel%) + 1, hibyte%

PRINT
PRINT "DAC has been programmed."
PRINT "Due to the 12-bit resolution of the DAC, you should expect "
PRINT USING "to see a voltage of #.### "; expected#

WaitForUser
GOTO ProgCh

Quit:
CLS
PRINT "Quick Basic sample #3 complete."
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


FUNCTION Deci% (DS AS STRING)
  Deci% = VAL("&H" + DS)
END FUNCTION

SUB WaitForUser
   LOCATE 23, 1
   PRINT "Press any key to continue ... "

   Key$ = ""
   WHILE Key$ = ""
	  Key$ = INKEY$
   WEND
END SUB