oDistance Object

Description
Operation
Properties

Examples
Related
Version History & Bug list

The oDistance Object manages a signed 8-Bit variable intended to be used as a URCP Distance value and that can be used in a virtual circuit. As well as the value of the variable, status properties are also provided that can be used in a virtual circuit.

The oDistance Object has properties and methods that support the URCP Distance value.

URCP Distance values deal with Distances, Lengths, Proximities. The common numbering system chosen for this is 64 steps per foot. 256 steps over a 4 foot range is used so that a single byte can represent a "Personal space" of 4 feet for a robot. This gives a resolution down to better than one fifth of an inch or about one half of a centimeter.

The oDistance2 Object is composed of two bytes. The second byte represents an extension to the first and can indicated distances of up to 512 feet.

Objects such as the oSonarDV and the oIRRange use URCP Distance values.

There are three main differences between this object and a standard Char variable.

This Object's Value property is an instance of the oValue Object which can be pointed to by a Virtual Circuit.
This Object maintains status bits which can be pointed to by Virtual Circuits.
This Object is 1 byte larger in order to store the status information.

The following table lists the size and availability of the oDistance Object.

Object	Size	Description	A1	A2	B1	B2	C1
oDistance	2 Bytes	An Object that manages a URCP distance value.			x	x	x
oDistance2	3 Bytes	An Object that manages a URCP distance value.			x	x	x

Operation:

An oDistance Object variable stores a signed 8 or 16 Bit value in its Value property and maintains other values that represent the status of those 8 bits.

The Negative property indicates the Most-Significant-Bit of the value which is used to indicate when the value is a negative number.

The NonZero Property indicates if the value is not zero.

Properties:

The following table lists the properties of the oDistance Object:

Property
Description

Value

The distance value.

Object Class: oValue Value Range: -32,768 to +32,767 or -128 to -127

Data Type: Numeric Default Value: 0

Value Description

0 No distance

32

64 1 foot forward

96

127 2 feet forward

Negative

A value that indicates the Value property is less than zero.

Object Class: oLogic Value Range: 0 - 1

Data Type: Numeric Default Value: 0

Notes on virtual circuit usage: Not all implementations of the oDistance Object have a linkable Negative property. While all instance of the oDistance Object that you create in your programs will have a linkable Negative property, some of the ooPIC Objects create a custom oDistance Object instance that cannot.

Negative Description

0
The Value property is a Positive value.

1
The Value property is Negative Value.

NonZero

A value that indicates the Value property is more than or less than zero.

Object Class: oLogic Value Range: 0 - 1

Data Type: Numeric Default Value: 0

Notes on virtual circuit usage: Not all implementations of the oDistance Object have a linkable NonZero property. While all instance of the oDistance Object that you create in your programs will have a linkable NonZero property, some of the ooPIC Objects create a custom oDistance Object instance that cannot.

NonZero Constant Description

0 cvFalse
The Value property is zero.

1 cvTrue
The Value property is not zero.

Data

The data for the Value property.

Object Class: oVar1 Value Range: 0 - 255

Data Type: Numeric Default Value: 0

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

Example:

The following examples use the oDistance Object as implemented in the oSonarDV object.

Visual Basic Syntax

C and Java Syntax

'This program reads an oSonarDV
'Object and outputs the distance
'on Scott Edwards LCD.

Dim A As New oSonarDV
Dim D As New oLCDSE

Sub Main()
  A.IOLineE = 31
  A.IOLineP = 30
  A.Operate = 1  
  D.IOLine = 16 
  Do  
    A.Operate.Pulse(1,1,250)
    D.Clear
    D.VString = Str$(A.Distance/64)
  Loop  
End Sub

// This program reads an oSonarDV
// Object and outputs the distance
// on Scott Edwards LCD.

oSonarDV A = New oSonarDV;
oLCDSE D = New oLCDSE;

Void Main(Void){
  A.IOLineE = 31;
  A.IOLineP = 30;
  A.Operate = 1;
  D.IOLine = 16;
  Do{
    A.Operate.Pulse(1,1,250);
    D.Clear;
    D.VString = Str$(A.Distance/64)
  } While (1);
}

Basic Syntax

'This program reads an oSonarDV
'Object and outputs the distance
'on Scott Edwards LCD.

A As oSonarDV(31,30,cvOn)
D As oLCDSE(16)

Do  
  A.Operate.Pulse(1,1,250)
  D.Clear
  D.VString = Str$(A.Distance/64)
Loop