Recordarray.Clear(Recordarray, 0, 36)
        'bytes 0 - 8 used for patient details
        Recordarray(0) = CByte(dtDob.Text.Substring(0, 1)) << 4
        Recordarray(0) = Recordarray(0) Xor CByte(dtDob.Text.Substring(1, 1))
        Recordarray(1) = CByte(dtDob.Text.Substring(2, 1)) << 4
        Recordarray(1) = Recordarray(1) Xor CByte(dtDob.Text.Substring(3, 1))
        Recordarray(2) = CByte(dtDob.Text.Substring(4, 1)) << 4
        Recordarray(2) = Recordarray(2) Xor CByte(dtDob.Text.Substring(5, 1))
        Recordarray(3) = Asc(cbGender.Text)
        Recordarray(4) = CByte(dtTest.Text.Substring(0, 1)) << 4
        Recordarray(4) = Recordarray(4) Xor CByte(dtTest.Text.Substring(1, 1))
        Recordarray(5) = CByte(dtTest.Text.Substring(2, 1)) << 4
        Recordarray(5) = Recordarray(5) Xor CByte(dtTest.Text.Substring(3, 1))
        Recordarray(6) = CByte(dtTest.Text.Substring(4, 1)) << 4
        Recordarray(6) = Recordarray(6) Xor CByte(dtTest.Text.Substring(5, 1))
        Recordarray(7) = CByte(dtTestTime.Text.Substring(0, 1)) << 4
        Recordarray(7) = Recordarray(7) Xor CByte(dtTestTime.Text.Substring(1, 1))
        Recordarray(8) = CByte(dtTestTime.Text.Substring(2, 1)) << 4
        Recordarray(8) = Recordarray(8) Xor CByte(dtTestTime.Text.Substring(3, 1))
        'bytes 9 to 14 used for vital signs
        Recordarray(9) = CByte(tbTemp.Text.Substring(0, 2))
        ' this byte will store the decimal for the temp string AND the Ph string
        Try
            Recordarray(10) = CByte(tbTemp.Text.Substring(3, 1)) << 4
        Catch
            Recordarray(10) = 0
        End Try
        Recordarray(11) = CByte(tbHeart.Text)
        Recordarray(12) = CByte(tbSystolic.Text)
        Recordarray(13) = CByte(tbDiastolic.Text)
        Recordarray(14) = CByte(tbResp.Text)
        'bytes 15 to 19 for electrolytes and metabolites
        Recordarray(15) = CByte(tbSodium.Text)
        Recordarray(16) = CByte(tbPotassium.Text.Substring(0, 1)) << 4
        Try
            Recordarray(16) = Recordarray(16) Xor CByte(tbPotassium.Text.Substring(2, 1))
        Catch
        End Try
        Recordarray(17) = CByte(tbChloride.Text)
        Recordarray(18) = CByte(tbUrea.Text.Substring(0, 1)) << 4
        Try
            Recordarray(18) = Recordarray(18) Xor CByte(tbUrea.Text.Substring(2, 1))
        Catch
        End Try
        Recordarray(19) = CByte(tbCreatinine.Text)
        'bytes 20 to 23 for acid and base
        Recordarray(20) = CByte(tbPh.Text.Substring(0, 1)) << 4
        Try
            Recordarray(20) = Recordarray(20) Xor CByte(tbPh.Text.Substring(2, 1))
        Catch
        End Try
        Try
            Recordarray(10) = Recordarray(10) Xor CByte(tbPh.Text.Substring(3, 1))
        Catch
        End Try
        Recordarray(21) = CByte(CInt((tbBase.Text) + 11))
        Recordarray(22) = CByte(tbH.Text)
        Recordarray(23) = CByte(tbOxygen.Text)
        'bytes 24 to 29 for liver function
        Recordarray(24) = CByte(tbAlbumin.Text)
        Recordarray(25) = CByte(tbBilirubin.Text)
        Recordarray(26) = CByte(tbALT.Text)
        Recordarray(27) = CByte(tbALP.Text)
        Recordarray(28) = CByte(tbGGT.Text)
        Recordarray(29) = CByte(tbAST.Text)
        'bytes 30 to 31 for lipids
        Recordarray(30) = CByte(tbTrig.Text)
        Recordarray(31) = CByte(tbCholesterol.Text.Substring(0, 1)) << 4
        Try
            Recordarray(31) = Recordarray(31) Xor CByte(tbCholesterol.Text.Substring(2, 1))
        Catch
        End Try
        'bytes 32 to 34 for haematology
        Recordarray(32) = CByte(tbHaem.Text.Substring(0, 1)) << 4
        Try
            Recordarray(32) = Recordarray(32) Xor CByte(tbHaem.Text.Substring(2, 1))
        Catch
        End Try
        Recordarray(33) = CByte(tbRBC.Text.Substring(0, 1)) << 4
        Try
            Recordarray(33) = Recordarray(33) Xor CByte(tbRBC.Text.Substring(2, 1))
        Catch 
        End Try
        Recordarray(34) = CByte(tbWBC.Text.Substring(0, 1)) << 4
        Try
            Recordarray(34) = Recordarray(34) Xor CByte(tbWBC.Text.Substring(2, 1))
        Catch
        End Try


    End Sub