The following VBA Excel macros download random data from a SwiftRNG device through a named pipe connection to the entropy server for Windows. The code only works while the SwiftRNG entropy server is running. This is the recommended way to achieve maximum concurrent speed and performance. Before using the examples, make sure the SwiftRNG device is plugged into an available USB port and entropy-server.exe is running on the same system.

Retrieving a random VBA Integer into cell A1

Private Function getRandomInteger() As Integer
    
    Dim intFileNum%
    intFileNum = FreeFile
    Dim RequestHeaderBytes(1 To 4) As Integer
    Dim randomInteger As Integer
    
    ' Open the entropy server named pipe
    Open "\\.\pipe\SwiftRNG" For Binary Access Read Write As intFileNum
    
    ' Prepare the Entropy Server API request structure - requesting 2 bytes for the VBA Integer.
    ' For more information visit https://tectrolabs.com/docs/swiftrng/entropy-server-api/
    RequestHeaderBytes(3) = LenB(randomInteger)
    
    ' Send the request header to the entropy server in one shot
    Put intFileNum, , RequestHeaderBytes
       
    ' With no delay, receive the random Integer
    Get intFileNum, , randomInteger
    
    Close intFileNum
    
    getRandomInteger = randomInteger
    End Function

Sub Macro1()
    Dim rndInteger As Integer
    rndInteger = getRandomInteger()
    [A1].Value = rndInteger

End Sub

Retrieving a random VBA Double into cell A1

    Private Function getRandomDouble() As Double
    
    Dim intFileNum%
    intFileNum = FreeFile
    Dim RequestHeaderBytes(1 To 4) As Integer
    Dim randomDouble As Double
    
    ' Open the entropy server named pipe
    Open "\\.\pipe\SwiftRNG" For Binary Access Read Write As intFileNum
    
    ' Prepare the Entropy Server API request structure - requesting 8 bytes for the VBA Double.
    ' For more information visit https://tectrolabs.com/docs/swiftrng/entropy-server-api/
    RequestHeaderBytes(3) = LenB(randomDouble)
    
    ' Send the request header to the entropy server in one shot
    Put intFileNum, , RequestHeaderBytes
    
    ' With no delay, receive the random Double
    Get intFileNum, , randomDouble
    
    Close intFileNum
    
    getRandomDouble = randomDouble
    End Function

Sub Macro1()
    Dim rndDouble As Double
    rndDouble = getRandomDouble()
    [A1].Value = rndDouble

End Sub

Retrieving a random VBA Long into cell A1

    Private Function getRandomLong() As Long
    
    Dim intFileNum%
    intFileNum = FreeFile
    Dim RequestHeaderBytes(1 To 4) As Integer
    Dim randomLong As Long
    
    ' Open the entropy server named pipe
    Open "\\.\pipe\SwiftRNG" For Binary Access Read Write As intFileNum
    
    ' Prepare the Entropy Server API request structure - requesting 4 bytes for a VBA Long.
    ' For more information visit https://tectrolabs.com/docs/swiftrng/entropy-server-api/
    RequestHeaderBytes(3) = LenB(randomLong)
    
    ' Send the request header to the entropy server in one shot
    Put intFileNum, , RequestHeaderBytes
    
    ' With no delay, receive the random Long
    Get intFileNum, , randomLong
    
    Close intFileNum
    
    getRandomLong = randomLong
    End Function

Sub Macro1()
    Dim rndLong As Long
    rndLong = getRandomLong()
    [A1].Value = rndLong

End Sub