I have query that involves a cross-language operation, namely converting 4 SBytes to a signed integer. The source language for this operation is Java, which utilizes the ByteBuffer in order to extract a signed integer from the data stream. The inner workings of ByteBuffer are at best a black box to me, as I haven't been able to find any hints to what actually goes on when Java extracts the integer. [Code]
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I'm working with byte arrays and building and disassembling Int16/UInt16 and Int32/UInt32 from them. I'd like to not worry about the Sign bit until I return the final value and just have the code return the appropriate value for the data type that was requested to be converted to/from the byte array
View 3 RepliesI have been trying to compute the checksum for a line of hex code. This is to create a hex file which will be loaded onto an embedded micro.Some of you guys may not know how this is done so very briefly:
a line of hex bytes:
: 10 01 00 00 21 46 01 36 01 21 47 01 36 00 7E FE 09 D2 19 01 40
The underlined bytes are taken and summed. (in this case the decimal 960). and the bold is the checksum Only the 8LSB (or single least significant byte) is needed to compute the checksum... which in this case, 960 = 03C0 in hex, so only C0 is needed.Two's complement is then taken:
step 1) logical not of C0 which is
step 2) add one (integer)
BIN...........DEC...HEX
[code]....
So here is the code I have been using: (quick mention that in the string passed, the hex bytes are all grouped together, there are no space characters)
Public Sub CreateLine(ByVal Data As String)
'Dim BDataArray(DataLength) As Byte
Dim IDataArray(Data.Length) As Integer
[code]....
where i get into trouble is where i commented 'i get into trouble'. My code works, but it's rather crude Now, in that line i first convert the hex value (string) "SChecksum" into an integer. I want to NOT this, so I get my step 2 from my explanation. However, the results appears to be a signed logical NOT. which gives me the wrong answer. My hashed togther version simply subtracts 256 before the not, in order to give me the correct answer.
Basically, I would love for someone to chime in and point out the flaws in my function, and push me towards figuring out the 'proper' way of doing this. Also I can't quite wrap my head around what would happen in the case a string were passed to my function that is over 16 bits, but I imagine I would have to subtract a larger value than 256, before doing the NOT in this case?(whilst we're on the subject of functions, I've used a 'sub', in which case should I used a sub, and which case should I use a function?).
my goal is to
1.Take an file(exe,dll,etc)
2.Convert it into hex
3.place that hex values in a stack
4.Execute the values inside the stack to its original form(i.e. take the elements out of stack and then convert it to a compile format)
Imports System.IO
Sub Main()
Dim fileName As String = "ABC.exe"
[code]....
I'm trying to create a linked list of an array of integers. Why is the following implicit conversion required?
When I run the code that contains that conversion, I get the following error.
As a real-time data acquisition user control data (a packet of an array of bytes) arrives every second, is converted into an integer array and inserted into a linked list.
The most recently arrived data is painted as coordinates on a grid at the right of a PictureBox using Graphics.DrawLine (pen,X1,Y1,X2,Y2).
The oldest data (arriving 120 seconds ago) will be drawn at the leftmost portion of the Picturebox.
Why a linked list rather than a list? To display 120 views of time sequence data, the draw routine the most recently inserted node to a node that points to Nothing. How do I limit the length of the linked list to 120 nodes and always ensure that the last node points to Nothing?
Do While Not item Is Nothing
item = item.NextItem
Loop
i have seen many posts resolving issues with converting bytes to KB, MB and GB...how would i convert GB,MB and KB to bytes?
View 11 RepliesI would like to know how to convert a unisgned byte to signed byte
Atm I got this
a
Function readSignedByte() As SByte
'-128/127
Dim b As SByte
[Code]....
it doesn't work one that well works for numbers positive over 127 if lets say ReadByte() has 128 it would give overflow error which I don't want it to give I would like it to overflow the number to negivate value aka its signed value.
I have been looking for a way to convert bytes down into another unit and append the unit format to the end and return it. I have found a few posts about it but I didn't perticularly want to write that much code that they listed, so I designed "my own" (I'm sure I'm not the only one who has done this method).Since I am pretty new at all this, I was wondering if anyone could let me know if there are any problems with how it would process the information and perhaps make it faster.[code]
View 29 RepliesI made a thread about Converting Form Bytes to Text and I got the answer but I wanted to ask if I can do the Opposite (Convert Text To Bytes).
View 1 RepliesI've got the following simple code to convert Bytes to a Hex string :-
Code:
Shared Function BytesToHex(ByVal bytes() As Byte) As String
If bytes Is Nothing Then Return ""
Dim S As String = BitConverter.ToString(bytes)
[Code].....
The HexToBytes routine obviously can take a lot longer to complete than the BytesToHex routine and is noticeably slower when dealing with a lot of data. As I'm converting a lot of hex strings back to bytes, I wondered if there was a more efficient way of doing it without looping through the whole string as I am doing?
I am tasked with the job of reading the X and Y coordinate of a Text label from a "save file" of a 2D CAD drawing. I found the exact position of the coordinates in the file, but I still don't understand how to read them 100%. They aren't simple ASCII characters.First, I read the file byte by byte, and load them into a textbox seperated by spaces as numbers from 0 to 255. Here is an example X and Y coordinate
View 1 RepliesIve 2 buttons and 3 text boxes.Button 1 encrypts the data from textbox1 to bytes, converts it to string and display it in textbox2.Button 2 reads string from textbox2, converts it to bytes and decrypts it displaying it in textbox3 (textbox1 and 3 got to match).The encrypt/decrypt process works fine but the conversion from string to bytes is failing and cannot seem to find the problem. The error states that the string doesnt have the same format (Bytes(i) = Byte.Parse(Values(i))
[Code]...
This has to be incredibly simple, but I must not be looking in the right place.
I'm receiving this string via a FTDI usb connection:
'UUU'
I would like to receive this as a byte array of
[85,85,85]
In Python, this I would convert a string to a byte array like this: [ord(c) for c in 'UUU']
I've looked around, but haven't figured this out. How do I do this in Visual Basic?
I am having trouble converting the Bytes() to a readable text.
I will be receiving packets from a UDP Connection, but due to lack of connectivity issues, they have provided me a .mem file that i am assuming is the whole stream of the packet.
So for now, i am trying to read the file and i get a collection of bytes(). but i cannot convert it to readable text.
I want to take a number such as 600 (0x0258) and send these hex values to a C-based system which is assigning char's to the received bytes and rebuilding to the original number. Currently, I am converting to bytes in VB.Net but it is not giving me the expected outcome (because of the ascii nature of the transfer most likely) [Code] I've also tried using Hex but this doesn't get the data in the correct format.
View 5 RepliesI am a .net beginner trying to make a crossover from vb6. I am trying to copy bytes of integer to a variable but I am getting this error msg. PInvokeStackImbalance was detected
A call to PInvoke function 'Tutorial_Class Dog!WindowsApplication1.ModAPIFunc::CopyMemory' has unbalanced the stack. This is likely because the managed PInvoke signature does not match the unmanaged target signature. Check that the calling convention and parameters of the PInvoke signature match the target unmanaged signature.
Module ModAPIFunc
Public Declare Sub CopyMemory Lib "kernel32" Alias _
"RtlMoveMemory" (ByVal Destination As Long, ByVal _
Source As Byte, ByVal Length As Integer)
[CODE]..........................
I am reading and writing binary data through a serial port and must (a) reassemble the incoming four bytes that make up a IEEE single-precision float into an actual float, and (b) disassemble a float into its four constituent bytes before squirting them through the serial port.
I am using VB.NET 2008. In VB6, I could use the LSET command, as in:
Code:
Private Type typByteArray
B(1 To 4) As Byte
End Type
[Code]....
But of course this code won't work in VB.NET. In C it would be easy to handle situations like this by using unions, but VB.NET doesn't support them.
I have a string of bytes which I am reading from a microcontroller via a serial port which is as follows : 02 10 18 14 CB 73 43 D3 14 00 0D 00 09 00 1B 00 04 B8 3C 00 00 24 00 30 AB
I would like to write some code to place each the bytes into an array with each element of the array consisting of one byte each.
I get an InvalidCastException was unhandled on converting the .value to .text but I can't figure out how to convert it. Tried a few different ways but nothing seems to work. load a file from disk and have that be assigned to the trackbar.value?
Dim FileName = (App_Path() & "SettingsPingTimeout.txt")
If File.Exists(FileName) Then
lblPingTimeout.Text = "Ping Timeout: " &
[Code]....
I want to convert some integer number to char. Basically i am writing these char to serial port to get response from modbus implemented hardware.
TempStr = Convert.ToChar(gSlaveNo) & Convert.ToChar(HOLDING_REGISTER_READ) & Convert.ToChar(writeAddressHigh) & Convert.ToChar(writeAddressLow) & Convert.ToChar(noOfRegistersHigh) & Convert.ToChar(noOfRegistersLow)
[code].....
I am trying to write a function which accepts a string as input and gives the integer as output,The string can be in any of these format for ex:2,500.75 or 2.500,7501 or 2'500.7513 or 2500,254 the output of function should be like 2500.56 Basically trying to get rid of the thousand separator which can be either a comma,or apostrophe. ..
View 6 RepliesI'm trying to make to do a widening conversion from a byte to an integer. form has a text box for both Input, and Output, plus a conversion button. [Code] I'm trying to use a catch block, but I'm not certain how it works exactly, and also tried to use an If statement to avert the issue, but that didn't work either. When ever user inputs a number greater than what can be held within the Byte data type the program crashes from the run time error. [Code] and an error message pops up in the compiler saying overflow exception was unhandled.
View 19 RepliesHeres my code:
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim product As String
[Code]....
Its says conversion from String to Integer not valid for this line: sales = InputBox("Please Enter Your Product Sales: ")
Also, when the first messagebox comes, how can I make it when you select "cancel", the programme then exits the sub routine and a second messagebox dosent come up?
So, yes, I've tried with these three formats, and the problem remains the same:I have a string, "s"For Each s As String In stringarray and this array is recieving data from a streamreader that is reading a csv file. The data I'm having dificulty reading are these very specific numbers(yes, only these numbers, because phone numbers get home safe and sound).The numbers I'm talking about are usually decimal.ValueList.Add(Convert.ToDecimal(s))
Now, when I convert them like that, they always bring a "D" alongside with them. I've personally checked the string multiple times, and it just has a "1", and somehow, my list recieves "1D" as a number, same thing happens with decimal numbers(0.29D for example). I've tried with Doubles and Integers, the result is the same.
If I want to populate an ArrayList with values 1 and 2 it works.[code]I found here a link about string to integer conversion in visual basic but I don't know how to deal it to my problem.
View 2 RepliesIs there any function in VB.NET to take the string "twenty" and convert it to 20?
View 2 RepliesWhat would be the best method of converting an integer to time?
253 would be 00:02:53 123456 would be 12:34:56 1 would be 00:00:01 etc
Can I use convert.todatetime?
I have a textbox which the user will enter a number into. I then have a label control which will perform a maths operation and write out the resulting answer; atleast this is whant I want anyway however this is not happening.
The code I have so far is
Protected Sub btnWork_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnWork.Click
Dim Work As Integer
[Code].....
I'm working on some code in VB that can get the average time from the speed of button press. I've got the maths done however I'm having a problem converting a TimeSpan declaration into a Integer where it can be divided and made into a average.
Maths for code:
2nd click
click count = 2
average= current time / 1
so current = time click count - 1
[code]....
I'm quite a newbie in VB.NET (and VB on the whole). So my question could sound rather odd, but still. I've stumbled upon an issue with the CInt and converting a double to an integer.
The issue is the following: CInt(10.5) would be 10
CInt(10.51) would be 11, but I expected 10... (Got used to C# style conversion: (int)10.51 would be 10)
As pointed out here Integer.Parse VS. CInt the result is just rounded in some fashion. Nowever, all I need is to get only integer part and throw away the fractional one. How can I achieve such type of conversion in VB.NET? After a short research I assume that I can use Fix() funciton to do the trick, but is it the best choice ever?
