Excel Macro Sends Command When Prompted by AS400 Style System

Hi,

Let me begin by thanking everyone in advance for any assistance with this macro problem. A little background: I currently have a very simple Excel macro that will send information contained in cells, one cell at a time, to another macro I have created in an AS/400 style system. The AS/400 style system will prompt for information (for example, name), and the Excel macro will send that information to the prompt, simulate Enter key (creating a new prompt in the AS/400 system), move to the next cell, send the information, etc. over and over until it reaches the last cell with information.

This works fine, however, the only way I know of "timing" the sending of information from Excel is using .Wait Now + TimeValue("0:00:01"). The issue with this is, sometimes the AS/400 system will hang after simulating Enter keystroke, but the Excel macro continues running at a single pace, resulting in some information not being sent properly. Furthermore, if Excel could send information when prompted, instead of waiting a second for each command, my process could be significantly sped up.

My question: is there some kind of way to build into the Excel macro to only send information when a valid prompt is up in the AS/400 system? I have attached a picture of the AS/400 type of prompt I'm speaking of, as well as my very simple macro to feed information to the system.

Const CA = "AS/400 System"
Const XL = "Microsoft Excel"

Sub QuickJournal()
   ' Quickly processes journals in (CA) window
   
   Dim AMOUNT As String
   Dim SYMBOL As String
    
   Do Until ActiveCell = ""
   
   SYMBOL = ActiveCell.Value
   
   AppActivate (CA)
   
   With Application
    .Wait Now + TimeValue("0:00:01")
    .SendKeys SYMBOL
    .Wait Now + TimeValue("0:00:01")
    .SendKeys ("~")
    End With
    
    AppActivate (XL)
    
    ActiveCell.Offset(0, 1).Activate
    
    AMOUNT = ActiveCell.Value
    
    AppActivate (CA)
    
    With Application
    .Wait Now + TimeValue("0:00:01")
    .SendKeys AMOUNT
    .Wait Now + TimeValue("0:00:01")
    .SendKeys ("~")
    End With
    
    AppActivate (XL)
    
    ActiveCell.Offset(1, -1).Select
    
    Loop
    
    With Application
    .Wait Now + TimeValue("0:00:01")
    End With
    
End Sub

Again, any assistance with this question is greatly appreciated!