Reading a Double value from memory

5 posts in this topic

#1 ·  Posted

Hi guys and gals,

I do IT support for a school, and they recently bought a no-name Chinese laser engraver for one of their classes. This thing has really basic software and hardly any documentation. My problem is that I want to create a script that alerts me (or a teacher) when it is done running a job, but it has no API or web interface or anything like that. I hate this machine, but it's my job to support it :/

I know the amount of Gcode steps that are required for a given job, so I was able to find the memory address in CheatEngine. I am attempting to read it with Nomadmemory.au3.

The value required is a Double, which apparently AutoIt does not play nicely with. I researched this for a few hours and didn't have any luck. I've run the variable against command like IsArray, IsBinary, IsNumber, etc.

The value is:

- A double, 8 bytes

- Is not a fraction

- Not an array

- Not a binary

- Is a number

- Is not hex

- Is not a string


So basically, I'm stumped as to how to read this value and turn it into a variable that my script can work with. I just need to logically compare it to my known amount of steps (173, in my case) and act based on that. I've tried converting the double value using Number, Int, Dec, Hex, etc., and calling the Double flag where applicable. No luck - it always shows $steps as a 0.

My (very rough) code:

#include <NomadMemory.au3>
#include <WindowsConstants.au3>
#include <MsgBoxConstants.au3>
#include <String.au3>
SetPrivilege("SeDebugPrivilege", 1)

$dAddress = 0x0A65A4D8  ;;gcode steps count

$MemOpen = _MemoryOpen(ProcessExists("cdscutter_x86.exe"))
While 1
   $steps = Number((_MemoryRead($dAddress, $MemOpen)),2)

 If $steps >= 173 then
 Func alert ()
 ;;placeholder - email or Prowl alert;;


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#2 ·  Posted

Can't edit my original post?

Also meant to say that I can successfully read values from this program when they are 4-byte integers, but doubles don't work at all.

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#3 ·  Posted

@potatos_x86: Welcome to the forums.:)

I would suggest you load the value into a struct (check out DllstructCreate and related commands in the Help), and then read the value from the struct. I can assure you that AutoIt most definitely supports doubles; I use them all the time.

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#4 ·  Posted

Ok, I've pasted this together with guidance from the DllStructCreate remarks, but it only passes zeroes.

Do you guys know what I'm doing wrong? Not sure if I need to specify that it's byte data, or specify that its source is a double. Deeply confused and would appreciate any input.


Local Const $tagSTRUCT1 = "struct;byte var1;byte var2;byte var3;byte var4[128];endstruct"
DllStructSetData($tSTRUCT1, "var4", ((_MemoryRead($dAddress, $MemOpen))))

 MsgBox($MB_SYSTEMMODAL, "", "Struct Size: " & DllStructGetSize($tSTRUCT1) & @CRLF & _
            "Struct pointer: " & DllStructGetPtr($tSTRUCT1) & @CRLF & _
            "Data:" & @CRLF & _
            DllStructGetData($tSTRUCT1, 1) & @CRLF & _ ; Or "var1" instead of 1.
            DllStructGetData($tSTRUCT1, "var2") & @CRLF & _ ; Or 2 instead of "var2".
            DllStructGetData($tSTRUCT1, 3) & @CRLF & _ ; Or "var3" instead of 3.
            DllStructGetData($tSTRUCT1, 4)) ; Or "var4" instead of 4.


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#5 ·  Posted

Your code doesn't create the structure.

Provided the address is correct, what does this give?

Local $dAddress = 0x0A65A4D8  ;;gcode steps count address (example)

Local $tNbSteps = DllStructCreate("double", $dAddress)
DllStructSetData($tNbSteps, 1, (_MemoryRead($dAddress, $MemOpen)))

 MsgBox($MB_SYSTEMMODAL, "", "Struct Size: " & DllStructGetSize($tNbSteps) & @CRLF & _
            "Struct pointer: " & DllStructGetPtr($tNbSteps) & @CRLF & _
            "Data:" & @CRLF & DllStructGetData($tNbSteps, 1))


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