oFeedBack1T Object

Main Index

Object List

Description
Operation
Properties

Examples
Connections
Related
Version History & Bug list

Description:

The oFeedBack1T Object is an I/O Function Object that times the signal return time in a feedback loop.

Whether or not the feedback is detected and how long it took to receive the feedback is reported.

The following table lists the size and availability of the oFeedBack1T Object.

	Object	Size	Description	A1	A2	B1	B2	C1
	oFeedBack1T	6 Bytes	Measures the time interval between a signal sent on one I/O line and returned on a second I/O line.			x	x	x

Operation:

When the oFeedBack1T Object's Operate property transitions from 0 to 1, a signal is sent out the I/O line specified by the IOLineS property, the Sent property is set to 1 and the Received property is cleared to 0.

After the signal is sent, the oFeedBack1T Object waits for the feed back indicating that the sent signal was detected by the I/O Line specified by the IOLineR property. While it is waiting, a counter increments every 13.83us. Once the feedback is detected, the current counter value (which is the time it took for the feedback to be detected) is stored in the Duration property, the Sent property is cleared to 0 and the Received property is set to 1.

If the feedback signal was not detected by the time that the counter reaches 4095 (Approximately 1/20th of a second), then the Sent property is cleared to 0, the Received property is set to 0. and the Timeout property is set to 1.

The feedback signal is sent once for each time that the Operate property transitions from 0 to 1. This is different than most of the other ooPIC Objects which continually update the properties.

Properties:

The following table lists the properties of the oFeedBack1T Object:

Property
Description

Duration

A value that indicates the duration between outputting the signal and detecting the feedback signal.

Object Class: oInt Value Range: 0 - 32768

Data Type: Numeric Default Value: 0

The duration is in 13.83us increments.

Sent

A value that indicates that the sending signal was outputted.

Object Class: oLogic Value Range: 0 - 1

Data Type: Numeric Default Value: 0

Sent Constant Description

0 cvFalse The feedback signal has not been sent.

1 cvTrue The feedback signal has been sent and the oFeedBack1T is waiting for its return.

Received

A value that indicates that the feedback signal was detected.

Object Class: oLogic Value Range: 0 - 1

Data Type: Numeric Default Value: 0

Received Constant Description

0 cvFalse
The feedback signal has not been detected.

1 cvTrue The feedback signal was detected.

TimeOut

A value that indicates that the feedback signal was not received in the allotted amount of time.

Object Class: oLogic Value Range: 0 - 1

Data Type: Numeric Default Value: 0

Timeout Constant Description

0 cvFalse
An feedback signal was detected or the oFeedBack1T is still waiting to detect the feedback signal.

1 cvTrue An feedback signal was still not received after a short period of time.

IOLineS

A value that specifies which I/O Line is used to output the sending signal.

Object Class: oIOLine Value Range: 0 - 31

Data Type: Numeric Default Value: 0

Some I/O Lines have special purposes. Be sure to see oIOLine help file for details.

Option

A value that selects if the sent signal is a pulse or a state change.

Object Class: oSelect0to1 Value Range: 0 - 1

Data Type: Numeric Default Value: 0

Option Description

0 The feedback signal is sent by pulsing the active state.

1
The feedback signal is sent by changing to the active state.

InvertS

A value that selects if the sending signal output is inverted.

Object Class: oSelect0to1 Value Range: 0 - 1

Data Type: Numeric Default Value: 0

InvertOutS Description

0
The feedback signal is sent by outputting 5 Volts.

1 The feedback signal is sent by outputting 0 Volts.

Availability: This property was added if firmware version C.1

IOLineR

A value that specifies which I/O Line is used to input the received feedback signal.

Object Class: oIOLine Value Range: 0 - 31

Data Type: Numeric Default Value: 0

Some I/O Lines have special purposes. Be sure to see oIOLine help file for details.

InvertR

A value that selects if the received feedback signal is inverted.

Object Class: oSelect0to1 Value Range: 0 - 1

Data Type: Numeric Default Value: 0

InvertInR Description

0
The feedback signal is detected by inputting 5 Volts.

1 The feedback signal is detected by inputting 0 Volts.

Availability: This property was added if firmware version C.1

Operate

A value that selects when to send the feedback signal.

Object Class: oOperate Value Range: 0 - 1

Data Type: Numeric Default Value: 0

Operate Constant Description

0 cvOff
The feedback signal is not sent.

1 cvOn
The feedback signal is sent once.

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

Examples:

In the following example, the oFeedBack1T Object is used.

Visual Basic Syntax

C and Java Syntax

'This program reads an oFeedBack1T
'Object and outputs the time
'on Scott Edwards LCD.

Dim A As New oFeedBack1T
Dim D As New oLCDSE

Sub Main()
  A.IOLineR = 31
  A.IOLineS = 30
  A.Operate = 1  
  D.IOLine = 16 
  Do  
    A.Operate.Pulse(1,1,250)
    D.Clear
    D.VString = Str$(A)
  Loop  
End Sub

// This program reads an oFeedBack1T
// Object and outputs the time
// on Scott Edwards LCD.

oFeedBack1T A = New oFeedBack1T;
oLCDSE D = New oLCDSE;

Void Main(Void){
  A.IOLineR = 31;
  A.IOLineS = 30;
  A.Operate = 1;
  D.IOLine = 16;
  Do{
    A.Operate.Pulse(1,1,250);
    D.Clear;
    D.VString = Str$(A);
  } While (1);
}

Basic Syntax

'This program reads an oFeedBack1T
'Object and outputs the time
'on Scott Edwards LCD.

A As oFeedBack1T(31,,,30,,cvOn)
D As oLCDSE(16)

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

Connections:

See the oSonarDV and oSonarPL Objects for connection examples.