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Properties, Methods, and Events

About ¾ (Method) Display the AboutBox.

CommPort ¾ (Property) Com1 through Com16 are valid.  Select the serial port used.

GetAll ¾ (Method) Returns a Boolean (True if communications with module succeeds). Retrieve all analog and digital input values.  Data may then be read using the GetChannel and ReadIO methods.  See also, the GetPrimaryChannel and GetIO methods.

GetChannel  ¾ (Method) Returns a Single.  GetChannel syntax is:  ChannelData = GetChannel (ChannelNumber), where ChannelNumber is a Byte representing the analog channel number (0-10).

GetIO ¾ (Method) Returns a Boolean (True if communications with module succeeds).  Retrieve digital I/O channels, both output and input.  This method is called by GetAll, but may be called independently.

GetPrimaryChannel ¾ (Method) Returns a Boolean (True if communications with module succeeds). Retrieve only Channel 0 analog data.  See also, the GetAll and GetIO methods.

Maximum ¾ (Property) Single.  Specify the Maximum analog input.  This usually is a voltage, but may be some other unit.  See also, the Minimum and Units properties.  Maximum must always be >= than Minimum.  Maximum will often be equal to VRef+ input to the SDA module, however, it actually is used to specify the scaled maximum input value.  Signal conditioning on the analog inputs can be used to allow the module to measure virtually any static of slowly changing input signal.

Minimum ¾ (Property) Single.  Specify the Minimum analog input.  This usually is a voltage, but may be some other unit.  See also, the Maximum and Units properties.  Minimum must always be <= Maximum.  Minimum will be 0, if VRef- input on the SDA module is connected to ground, and if no signal conditioning is used to offset the minimum input positive or negative.

Note: The difference between Maximum and Minimum specifies the "span" of input values.  If Maximum = 2.23 volts and Minimum = -2.23 volts, signal conditioning should be used to either amplify and shift the actual input maximum voltage to 5 volts, and the actual minimum input voltage to 0 volts, or the SDA module's VRef+ input should be connected to +2.23 volts, and VRef- input to -2.23 volts.  Any other variation will reduce the dynamic range of the A/D converter, or (in the worst case) can damage the module.  Read the SDA manual to make sure that it will handle the actual voltage ranges that you will be applying.

ModelType ¾ (Property) Specify the SDA model that is used, SDA10 or SDA12.  This property will be used with the Maximum and Minimum properties to convert A/D values to calculate the Single precision values that are obtained by the GetChannel and PrimaryChannel properties.

PollAll ¾ (Property) Boolean.  Specify whether all channels will be polled if the TimerInterval is >= 55.  True enables polling of all analog channels.  False disables polling of all channels, but does not disable polling (both PollAll and PollPrimary must be False to disable all polling).

PollDataAvailable ¾ (Event)  The PollDataAvailable event is generated when a poll is completed.  See the PollAll, PollPrimary, and PollInterval properties.

PollInterval ¾ (Property) Long.  Specify the polling interval in milliseconds that will be used if PollAll or PollPrimary are True.  Valid values are 55-65536.

PollPrimary ¾ (Property) Boolean.  Specify whether only Channel 0 will be polled if the PollInterval is >= 55.  True enables polling of only Channel 0.  False disables polling of Channels 0, but does not disable polling (both PollAll and PollPrimary must be False to disable all polling).

PrimaryChannelData ¾ (Property) Single.  Read only.  Returns the most recent value for analog Channel 0.  

ReadIOData ¾ (Method) Returns a Boolean.  Specifies the logical I/O value for the specified I/O channel.  Syntax is IOData = ReadIOData (IOChannelNumber), where IOCahnnelNumber is a byte with a range of 0-5.  Channels 0-2 are Inputs, while Channels 3-5 reflect values set using the SetIO method.

SDAEnable ¾ (Property) Boolean. Enable or disable communications with the SDA module.  If SDAEnable is False, commands will not be sent to the serial port, and serial data will not be read.  However, attempt to send commands or to read will not result in an error.  This allows simple override, while retaining polling properties, etc.

SetIO ¾ (Method) Set or reset digital output.  Syntax is: SetIO (IOChannelNumber) = True/False, where IOChannelNumber = 0-2.

Timeout ¾ (Property) Integer.  Specify the number of milliseconds to wait for a response to a command to an SDA module to read analog or digital inputs.  The minimum value is 20 mS.

Units  ¾ (Property) Enum.  Specify the Units string that will be returned by the UnitsString method.  None = 0
V = 1
mV = 2
A = 3
mA = 4
F = 5
C = 6

UnitsString  ¾ (Method) Enum.  Returns a string equivalent to the number set using the Units property.

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Last modified: 11/25/09