Creating Countdown timer

Hello,

I'm trying to create a count down timer using a specific time I have already figured. For instance i have a time of "01:30:00". I'm wanting to incorporate a button into my sheet that starts counting down 1 second at a time. Ive tried using a formula that would work for excel but it doesn't seem to work for zoho. When i run the macro it comes up as an error saying "date + date not implemented". I've tried a few different things with no result. With never being formally trained and self taught I don't even know where to start.

Here's the excel version of a simple counter.

Dim gCount As Date
'Updateby20140925
Sub Timer()
    gCount = Now + TimeValue("00:00:01")
    Application.OnTime gCount, "ResetTime"
End Sub
Sub ResetTime()
Dim xRng As Range
Set xRng = Application.ActiveSheet.Range("E1")
xRng.Value = xRng.Value - TimeSerial(0, 0, 1)
If xRng.Value <= 0 Then
    MsgBox "Countdown complete."
    Exit Sub
End If
Call Timer
End Sub

This simple counter brings back the same error "date + date not implemented". 

So simply i want to take a time from cell ("J8") hit a "start" button and run a macro that simply counts down the time to "zero". Is this function possible in zoho or no? 