oDIO1 Object

• Description
• Operation
• Properties
• Methods

• Examples
• Related
• Version History & Bug list

The I/O line can be set to read the electrical state presented on them or set to output a specified electrical state.

The difference between this object and the oIOLine Object is that oIOLine will use 1 byte of variable memory while the oDIO1 uses 1 byte of object memory.  This can be an important difference when creating large programs. 

An oDio1 Object's State property represents the electrical state of the I/O line specified by the IOLine property. The Direction property specifies if the I/O Line is an input or an output.

The State property can be pointed to by a Virtual Circuit.  This allows a Virtual Circuit to output a calculated value on the I/O Line once each Object List Loop.

When the Direction property is 1 (an input), the electrical state of the specified I/O Line is copied to the State property once each Object List Loop.

When the Direction property is 0 (an output), the electrical state of the specified I/O Line is set to the state of the State property once each Object List Loop.

When the IOLine property is set, the Direction property is updated to reflect the current state of the specified I/O Line.
Note that this means that you MUST set the IOLine property before you set the Direction property for the Direction property to affect the I/O line you want to use.

The IOLine property is an instance of the oIOLine object which is created when the oDIO1 object is.  The oDIO1 object uses the oIOLine Object to do the actual I/O to the I/O line.  Since the default property of the oIOLine specifies which I/O line to work with, then the IOLine property can be directly specified.  Example: IOLine = 1. (see oIOLine object for more detail)

Caution: the I/O lines in I/O lines 16 - 23 are used for special purposes such as PWM, serial input/output and DDELink.  Be sure that you are not attempting to reuse them if the special functions are in use.

The following table lists the properties of the oDIO1 Object:

Property	Description
State	A value that indicates the electrical state to the I/O Line. Object Class:  oBit   Value Range:  0 - 1 Data Type:  Numeric   Default Value:  0 State Constant Description 0 cvOff The specified I/O line is at 0 Volts. 0 (Logic) cvLow The specified I/O line is at 0 Volts. 0 (Voltage) cvPressed A Switch connected to theoDio1 Object instance is pressed connecting the I/O line to ground. 1 cvOn The specified I/O line is at +5 Volts. 1 (Logic) cvHigh The specified I/O line is at +5 Volts. 1 (Voltage) cvUnpressed A Switch connected to theoDio1 Object instance is not pressed leaving the I/O line at +5 Volts.
IOLine	A value that specifies the I/O line to use. Object Class:  oIOLine   Value Range:  0 - 31 Data Type:  Numeric   Default Value:  0 IOLine Constant Description 0 cvOff The instance of the oDio1 Object is inactive and the processing time is freed for other Objects. 1 - 31   The oDio1 Object uses the pin specified for its I/O Some I/O Lines have special purposes.  Be sure to see oIOLine help file for details.
Direction	A value that specifies if the I/O line is used as an input or an output. Object Class:  oProperty   Value Range:  0 - 1 Data Type:  Numeric   Default Value:  0 Direction Constant Description 0 cvOutput The specified I/O Line is an output and the State property is written to it. 1 cvInput The specified I/O Line is High-Z and the State property is read from it.
IsLow	A value that indicates if the current state is Low. Object Class:  oProperty   Value Range:  0 - 1 Data Type:  Numeric (Read-Only)   Default Value:  (Not State) The IsLow property reports the reverse value of the State property.  It is worded to be understood in an evaluation such as: if X.IsLow then... IsHigh Description 0 The Electrical State is at a Logical High (5 Volts). 1 The Electrical State is at a Logical Low (0 Volts).
IsHigh	A value that indicates if the current state is High. Object Class:  oProperty   Value Range:  0 - 1 Data Type:  Numeric (Read-Only)   Default Value:  (State) The IsHigh property reports the same value as the State property.  It is worded to be understood in an evaluation such as: if X.IsHigh then... IsHigh Description 0 The Electrical State is at a Logical Low (0 Volts). 1 The Electrical State is at a Logical High (1 Volts).
Address	Returns a pointer to the address of the oCounter Object instance. Object Class:  oAddress   Value Range:  0 - 127 Data Type: Pointer (Read Only)   Default Value:  Address of Object

'This program turns an output on and 'then off at a rate of once a second. Dim A As New oDio1 Sub Main() A.IOLine = 31 A.Direction = cvOutput Do A.Invert ooPIC.Delay = 100 Loop End Sub

Bugs: No known bugs.