TV IR Remote Controlled Robot

So this is my first AVR project which i thought is worth to share.
It is a simple Robot which is controlled by my TV remote.

How does It Work
IR Communication:
TV remotes uses Infra-red signals to communicate to TV. Remote have IR LED which sends IR signals. At receiving end (TV) has a IR receiver (normally TSOP 1738 sensor) to receive signals sent via remote. In Many remotes you can see IR LED on the front of the remote. Every button on Remote have a unique code which is stored in both TV and Remote memory. So whenever we press a button IR LED sends Code of the pressed Button to TV which then figure out code and take action accordingly.


TSOP 1738
This is the IR Receiver I have used in my project. It have 3 pins as shown below. OUT pin is the data pin which sends signals to Microcontroller. It is high by default that means when it has nothing to receive it will send 1 or +5v.

All buttons have individual code  
(... To be continue)

Complex Data Structure VBScript/QTP

VBScript data structures

Vbscript lacks support of complex data structures unlike other programming languages. This sometimes makes life a bit difficult. We need to code our own algorithms to achieve simple tasks like sorting of an array or reversing it.  .net has support for complex data structures which come with build-in functions for these simple tasks. So if we can use .net data structure then we can avoid reinvention of wheel for some of tasks. Well the good news is some of .net libraries are exposed to COM and can be used in vbscript.

Below are some examples:

1. CreateObject("System.Collections.ArraytList")
2. CreateObject("System.Collections.SortedList")
3. CreateObject("System.Collections.Stack")
4. CreateObject("System.Collections.Queue")
5. CreateObject("ADODB.RecordSet")  'Disconnected RecordSet - this is not related to .net yet useful

ArrayList:

Set objArrayList = CreateObject("System.Collections.ArrayList") objArrayList.Add 6 objArrayList.Add 8 objArrayList.Add 2 objArrayList.Add 4 objArrayList.Add 1 objArrayList.Add 5 objArrayList.Add 3 objArrayList.Add 3 objArrayList.Add 7 'unlike redefining array size (redim statement) every time before appening an element into an array, ' with arraylist you dont need to worry about that. 'Coverting ArrayList to legacy Array Debug.Print Join(objArrayList.ToArray, ",")  ' output: 6,8,2,4,1,5,3,3,7 'will give u element at mentioned index Debug.Print objArrayList(0)  ' output: 6 'this will give u size of arraylist                  Debug.Print objArrayList.Count   ' output: 9 'this will tell u if an element exists or not. no need to iterate over all elements Debug.Print objArrayList.contains(5) ' output: true 'this will sort elements. no need to write long algoritims objArrayList.Sort Debug.Print Join(objArrayList.ToArray, ",") ' output: 1,2,3,3,4,5,6,7,8 'this will reverse the order of all elements present objArrayList.Reverse Debug.Print Join(objArrayList.ToArray, ",") ' output: 8,7,6,5,4,3,3,2,1 'remove a specific element objArrayList.Remove 8   'This will remove 8 from arraylist no matter on which index it is on 'remove element by index objArrayList.RemoveAt 6   'This will remove element present at 6th index 'remove all elements objArrayList.Clear

For VBScript Dictionary Objects we don’t need to redim while appending/removing elements; also an element can be directly searched without iterating through each of them. Both of these features are available with ArrayList as well but one of the most important dictionary feature ‘Key-Value pair’ is not present in ArrayList. SortedList is alternative if you want utilize power of both ArrayList and Dictionary.

SortedList :

SortedList is sorted Dictionary. Every time we add/remove a key value pair in dictionary, its automatically gets sorted by Key. Also you can also access elements based on its index (just like arrays) which makes this even more powerful.

'For this example i am maintain employee name and joining date where joining date is the key Set objSortedList = CreateObject("System.Collections.SortedList") objSortedList.Add CDate("1-jan-2012"), "Ajay" objSortedList.Add CDate("3-Mar-2012"), "Amit" objSortedList.Add CDate("20-dec-2011"), "Jay" objSortedList.Add CDate("2-jan-2012"), "Vijay" ' All elements will be automatically sorted by Key (joining date in this case) 'Get Count of elements Debug.Print objSortedList.Count 'output : 4 'access element by its key Debug.Print objSortedList(CDate("1-Jan-2012")) 'output: Ajay 'accessing elements of dictionary by index For i = 0 To objSortedList.Count - 1     Debug.Print objSortedList.GetByIndex(i) Next 'Check if Keys Exists                                                                                           Debug.Print objSortedList.ContainsKey(CDate("1-jan-2012")) 'output: True 'Check if Value Exists Debug.Print objSortedList.ContainsValue("Vijay") 'output: True 'Get Index by Key (zero based index) Debug.Print objSortedList.IndexOfKey(CDate("1-jan-2012")) 'output: 1 'Get Index By Value Debug.Print objSortedList.IndexOfValue("Vijay") 'output: 2 'Remove Element by Key objSortedList.Remove CDate("1-jan-2012") 'Remove Element by Index objSortedList.RemoveAt 0 'Remove all elements objSortedList.Clear

 

Using Stack:

Set objStack = CreateObject("System.Collections.Stack") 'Adding elements in Stack objStack.Push "Item_1" objStack.Push "Item_2" objStack.Push "Item_3" objStack.Push "Item_4" 'Iterate through each element of Stack For Each Item In objStack     Debug.Print Item Next 'Convert Stack to Array Debug.Print Join(objStack.ToArray, ",") 'output: Item_4,Item_3,Item_2,Item_1 'Get Stack Element Count Debug.Print objStack.Count  'output: 4 'Check if an element exists or not Debug.Print objStack.Contains("Item_2") 'output: True 'Pop the last In element from Stack Debug.Print objStack.Pop    'output: Item_4 'Get Last in element without popping it out Debug.Print objStack.Peek   'output: Item_3 Debug.Print objStack.Pop    'output: Item_3 Debug.Print objStack.Pop    'output: Item_2 ‘Remove all elements from Stack objStack.Clear

Using Queue:

Set objQueue = CreateObject("System.Collections.Queue") 'Adding elements in Queue objQueue.Enqueue "Work_Request_ID_11" objQueue.Enqueue "Work_Request_ID_2" objQueue.Enqueue "Work_Request_ID_4" objQueue.Enqueue "Work_Request_ID_9" 'Iterate through each element of Queue For Each Item In objQueue     Debug.Print Item Next 'Convert Queue to Array Debug.Print Join(objQueue.ToArray, ",") 'output: Work_Request_ID_11,Work_Request_ID_2,Work_Request_ID_4,Work_Request_ID_9 'Get Queue Element Count Debug.Print objQueue.Count  'output: 4 'Check if an element exists or not Debug.Print objQueue.Contains("Work_Request_4") 'output: True 'Get the First In element from Queue Debug.Print objQueue.Dequeue    'output: Work_Request_ID_11 'Get first in element without removing it Debug.Print objQueue.Peek   'output: Work_Request_ID_2 Debug.Print objQueue.Dequeue    'output: Work_Request_ID_2 Debug.Print objQueue.Dequeue    'output: Work_Request_ID_4 'Clear Entire Queue objQueue.Clear

Disconnected RecordSets:

Multi-Level Sorting and Filtering: If you are dealing with data which more than just key value pair and fits best in 2D array, and you also wanted to perform sorting and filtering on it, then disconnected recordsets is excellent option.

(Although this is not related to .net but is quite useful in these situations)

Let’s say if I have below 2D array

EmpID	EmpName	EmpAge	JoiningDate
1	Ajay	27	5-Jan-2012
2	Vijay	28	5-Jan-2012
3	Jay	30	2-Mar-2012
4	Amit	26	20-Dec-2011

And you wanted to get employees who joined in 2012 and have age less than 30yrs, also you wanted to get data sorted on joining Date and if joining date is same then second level of sorting should be applied at Age (in decending order).

So output should look like

EmpID	EmpName	EmpAge	JoiningDate
2	Vijay	28	5-Jan-2012
1	Ajay	27	5-Jan-2012

Building this logic in plain Vbscript might be tedious and error prone, instead we can use a disconnected record set to first populate data and then filter and sort by using its internal function.

Const adDouble = 5 Const adVarChar = 200 Const adDate = 133 Set objRecordSet = CreateObject("ADODB.Recordset") objRecordSet.Fields.Append "EmpID", adDouble objRecordSet.Fields.Append "EmpName", adVarChar, 50 objRecordSet.Fields.Append "EmpAge", adDouble objRecordSet.Fields.Append "JoiningDate", adDate objRecordSet.Open objRecordSet.AddNew Array("EmpID", "EmpName", "EmpAge", "JoiningDate"), Array(1, "Ajay", 27, CDate("5-Jan-2012")) objRecordSet.AddNew Array("EmpID", "EmpName", "EmpAge", "JoiningDate"), Array(2, "Vijay", 28, CDate("5-Jan-2012")) objRecordSet.AddNew Array("EmpID", "EmpName", "EmpAge", "JoiningDate"), Array(3, "jay", 30, CDate("2-Mar-2012")) objRecordSet.AddNew Array("EmpID", "EmpName", "EmpAge", "JoiningDate"), Array(4, "Amit", 28, CDate("20-Dec-2011")) objRecordSet.Filter = "JoiningDate>'1-jan-2012' and EmpAge<30" objRecordSet.Sort = "JoiningDate, EmpAge DESC" objRecordSet.MoveFirst Do Until objRecordSet.EOF     Debug.Print objRecordSet("EmpID").Value & " | " & objRecordSet("EmpName").Value & " | " & objRecordSet("EmpAge").Value     objRecordSet.MoveNext Loop objRecordSet.Close

Label : QTP, vbscript, Array, Dictionary, RecordSet, ArrayList, Stack, Queue, SortedList, Sorting