excelmacros来解码用示波器数字化的串行线路信号（过采样）
我用示波器对232 UART进行了数字化处理。 我想写一个macros来解码在ASCII字符接收到的数据。 这里附上了这个文件。 信号从0移动到3伏。采样频率为1MHZ。 我可以从哪里开始？
http://www.tr3ma.com/Dati/C3lightbridge00004.txt
http://www.tr3ma.com/Dati/C3lightbridge00005.txt
我解决了。 根据串行线232的规范（你可以使用这个作为参考： https ： //wcscnet.com/tutorials/introduction-to-rs232-serial-communication/ ），并假定数据格式化，没有crc和奇偶校验etc.etc，我应该在采样信号中find一个起始位，8个数据位和一个停止位。 即使你有2个停止位和偶校验位，我的代码仍然可以正常工作。
所以，这是我写的macros：
Sub Serial232() ' ' Serial232 Macro ' ' Dim curSamplePos As Long Dim SamplingFrequency As Long SamplingFrequency = 1000000 '1MSps Dim SerialLineSpeed As Long SerialLineSpeed = 115200 '115200bps Dim oneBitDuration As Double oneBitDuration = 1 / SerialLineSpeed 'time in seconds (8,68us) oneBitDurationSamples = SamplingFrequency / SerialLineSpeed '8,68 Samples Dim signalThreshold As Double signalThreshold = 1.7 Dim totalNumberOfSamples As Long totalNumberOfSamples = ThisWorkbook.Worksheets(1).UsedRange.Rows.Count ' Rows.Count ' Range("B6").End(xlDown).Row 'color all che cells to white: Range("B6:B" & totalNumberOfSamples).Interior.ColorIndex = 0 Range("C6:C" & totalNumberOfSamples).Value = "" totalNumberOfSamples = ThisWorkbook.Worksheets(1).UsedRange.Rows.Count 'start from first sample, search the first transition (start bit) 'from 1 to zero Dim MachineStatus As String MachineStatus = "searchBegin" 'status of the processign statusMachine Dim BitAquired As Long 'it's the counter of the bits, from 1 to 8, inside the byte Dim currentByte As String 'it's the byte aquired in binary format Dim CompleteDecodedASCII As String CompleteDecodedASCII = "" Dim completeDecodedHex As String completeDecodedHex = "" Dim remainder As Double 'remainder from quantization (from oversampling of the bit) Dim hexByte As String 'temporary variable where the info about last byte is stored For curSamplePos = 6 To totalNumberOfSamples Range("B" & curSamplePos).Interior.ColorIndex = 37 Select Case MachineStatus Case "searchBegin" If (Val(Range("B" & curSamplePos).Value) < signalThreshold) Then Range("C" & curSamplePos).Value = "Wait..Status:searchingBegin" Else 'found the nothing Range("C" & curSamplePos).Value = "Wait..Status:beginOfEmptyArea" MachineStatus = "searchStartBit" End If Case "searchStartBit" If (Val(Range("B" & curSamplePos).Value) > signalThreshold) Then Range("C" & curSamplePos).Value = "Wait..Status:searchingStartBit" Else 'found the start bit Range("C" & curSamplePos).Value = "Wait..Status:beginOfStartBit" 'found begin of start bit 'now move to the middle of the start bit curSamplePos = curSamplePos + Int(oneBitDurationSamples / 2) If (Val(Range("B" & curSamplePos).Value) > signalThreshold) Then 'maybe we found a spike, let's report it, and ignore it Range("C" & curSamplePos).Value = "Error:Spike Found" Else Range("C" & curSamplePos).Value = "Wait..Status:middle Of start Bit" MachineStatus = "acquireBits" 'go to next status 'reset the variable for the byte that we are going to aquire BitAquired = 0 currentByte = "" remainder = 0 End If End If Case "acquireBits" 'aquire bits 'move on the next bit to acquire curSamplePos = curSamplePos + Int(oneBitDurationSamples) - 1 remainder = remainder + oneBitDurationSamples - Int(oneBitDurationSamples) If (remainder > 1) Then 'if we accumulated big remainder, add one sample curSamplePos = curSamplePos + 1 remainder = remainder - 1 End If If (Val(Range("B" & curSamplePos).Value) > signalThreshold) Then 'found 1 currentByte = "1" & currentByte Else 'found 0 currentByte = "0" & currentByte End If BitAquired = BitAquired + 1 Range("C" & curSamplePos).Value = "Wait..Status:middle Of Bit number " & BitAquired If (BitAquired = 8) Then 'byte completed 'print the output hexByte = Application.WorksheetFunction.Bin2Hex(currentByte) completeDecodedHex = completeDecodedHex & "-" & hexByte CompleteDecodedASCII = CompleteDecodedASCII & Chr(Application.WorksheetFunction.Bin2Dec(currentByte)) Range("C" & curSamplePos).Value = "This is the last bit of the byte. Current Byte in BIN:" & currentByte & ", in HEX:" & hexByte & ", in ASCII:" & Chr(Application.WorksheetFunction.Bin2Dec(currentByte)) 'cerchiamo il bit di stop MachineStatus = "searchStopBit" End If Case "searchStopBit" 'spostati al centro del bit di stop, che dovrebbe essere il prossimo curSamplePos = curSamplePos + oneBitDurationSamples - 1 If (Val(Range("B" & curSamplePos).Value) > signalThreshold) Then 'trovato stop bit Range("C" & curSamplePos).Value = "Wait..Status:middle Of Stop bit" Else 'found 0 but the stop bit should be 1 'report error Range("C" & curSamplePos).Value = "Error: Stop bit not found" End If 'quindi ora possiamo ricominciare tutto daccapo. curSamplePos = curSamplePos + 1 MachineStatus = "searchBegin" Case Else End Select DoEvents Next DoEvents Range("C" & curSamplePos).Value = "Data ended. currently processing data: Current Byte in BIN:" & currentByte & ", in HEX:" & hexByte & ", in ASCII:" & Chr(Application.WorksheetFunction.Bin2Dec(currentByte)) Range("C" & curSamplePos + 1).Value = "HEX Decoded Data: " & completeDecodedHex Range("C" & curSamplePos + 2).Value = "ASCII Decoded Data: " & cleanString(CompleteDecodedASCII) MsgBox "Done" End Sub Function cleanString(str As String) As String Dim outstr As String For i = 1 To Len(str) If (Mid(str, i, 1) = Chr(0)) Then outstr = outstr & " " Else outstr = outstr & Mid(str, i, 1) End If Next cleanString = outstr End Function 这是macros运行后的Excel文件：
http://www.tr3ma.com/Dati/C3lightbridge00003.xls http://www.tr3ma.com/Dati/C3lightbridge00004.xls http://www.tr3ma.com/Dati/C3lightbridge00005.xls