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CHAPTER 6 THE CALL DRIVER
MULTIPLE BOARD SYSTEMS
In systems with more than one board, more than one Handle must be used. The following example
opens the handles for two A X - 1 6 s and then takes an A/D reading from Channel 0 of the Board
1
and
from Channel 5 of Board 2.
BrdNum = 0
'First board
Derr = ADCl6GetDevHandle% (BrdNum, ADCl6A)
BrdNum
= 1
'Second board
Derr = ADC16GetDevHandle%(BrdNum,ADCl6B)
Chan
= 0:
Gain
= 0
Derr
=
KADRead%(ADC16A, Chan, Gain, ADValue)
PRINT "The first Board returned", ADValue
Chan = 5: Gain = 0
Derr
=
KADRead%(ADC16B, Chan, Gain, ADValue)
PRINT "The second Board returned", ADValue
Note that the first KADread uses the Handle of the first Board as Set up with BrdNum
=
0, while the
second KADRead uses the second Handle.
Other Immediate Operation commands include
KDIRead
KDO Write
Read the digital inputs
Write the digital outputs
FRAMES
Analog
Input and Digital Output allow for operation using Frames. For Digital Output the Frame is a
means of returning the value of the Digital Output port. For Analog Input the Frame is the group of all
setup parameters used in a synchronous or interrupt driven operation. For example, an A/D function
requires setting up the following parameters:
Input Channels to scan (Start and Stop channels).
InputGain.
Number of samples.
Data buffer location.
A complete set
of selections is a Frame. A complete definition of the above parameters would be
included in an A/D frame. Two
types
of Frames are available for the ADC-16, as follows: A/D
Frames and Digital Output Frames.
Program flow is similar in each
t y p e
of Frame, as follows:
First:
Next:
Then:
Optionally:
Open or get a Frame with KGetADFrame or KGetDOFrame.
Setup the parameters within the Frame.
Execute the desired Frame function.
Check the status of the operation initiated.
6 -
11
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