I'm trying my driver with Driver Verifier turned on in Windows 7 x64, and get IRQL_NOT_LESS_OR_EQUAL(0A) bugcheck. From analyze -v info, it seems that the memory page of RtlAnsiCharToUnicodeChar function gets paged out, so calling that function causes bugcheck 0A . RtlAnsiCharToUnicodeChar is an ntoskrnl.exe exported function. Can it really be paged out? If so, how can I prevent it?
On spot debug info screen shot below:
yes. of course - very many ntoskrnl routines in PAGE* section.
RtlAnsiCharToUnicodeChar also paged - read in documentation:
IRQL <= APC_LEVEL
also read about DbgPrintEx routine
DbgPrint and DbgPrintEx can be called at IRQL<=DIRQL. However, Unicode
format codes (%wc and %ws) can be used only at IRQL = PASSIVE_LEVEL.
and
However, the Unicode format codes (%C, %S, %lc, %ls, %wc, %ws, and
%wZ) can only be used with IRQL = PASSIVE_LEVEL.
so if you not use Unicode format you can use DbgPrint or KdPrint(this is macro) at any IRQL but if you use Unicode format - only on PASSIVE_LEVEL or APC_LEVEL (about APC_LEVEL i say by self)
You can try to use the MmLockPagableCodeSection on that specific routine to prevent it being paged out, however it's probably not advisable (and you don't know what dependencies it has, if they're located in pagable sections as well). In any case, make sure you read the documentation thoroughly.
A better approach is to run at Passive/APC level in the first place before invoking the printing function - e.g., by scheduling work item (you can also force lowering the IRQL with KeLowerIrql function but it's not advisable by MSFT).
Related
I'm using LabVIEW and its VISA capabilities to control a Keithley 2635A source meter. Whenever I try to identify the device, it works just fine, both in reading and writing.
viWRITE(*IDN?) /* VISA subVI to send the command to the machine */
viREAD /* VISA subVI to read output */
However, as soon as I set the voltage (or current), it does so. Then I send the command to perform a measurement, but I'm not able to read that data, with the error
VISA: (Hex 0xBFFF0015) Timeout expired before operation completed.
After that, I can not read the *IDN? output either anymore.
The source meter is connected to the PC via a National Instrument GPIB-USB-HS adaptor.
EDIT: I forgot to add, this happens in the VISA Interactive Control program as well.
Ok, apparently the documentation is not very clear. What the smua.measure.X() (where X is the needed parameter) command does is, of course, writing the measurement outcome on a buffer. In order to read that buffer, however, the simple viREAD[] is not sufficient.
So basically the answer was to simply add a print command: this way I have
viWRITE[print(smua.measure.X())];
viREAD[]
And I don't have the error anymore. Not sure why such a command is needed, but that's that. Thank you all for your time answering me.
As #Tom Blodget mentions in the comments, the machine may not have any response to read after you set the voltage. The *IDN? string is both command and query. That is, you will write the command *IDN? and read the result. Some commands do not have any response to read. Here's a quick test to see if you should be reading from the instrument. The following code is in python; I made up the GPIB command to set voltage.
sm = SourceMonitor()
# Prints out IDN
sm.query('*IDN?')
# Prints out current voltage (change this to your actual command)
sm.query('SOUR:VOLT?')
# Set a new voltage
sm.write('SOUR:VOLT 1V')
# Read the new voltage
sm.query('SOUR:VOLT?')
Note that question-marked GPIB commands and the query are used when you expect to get a response from the instrument. The instrument won't give a response for the write command. Query is a combination of write(...) and read(...). If you're using LabView, you may have to write the write and read separately.
If you need verification that the machine received your instruction and acted on it, most instruments have the following common commands:
*OPC? query to see if the operation is complete
SYST:ERR? query to see if any error was generated
Add a question mark ? to the end of the GPIB command used to set the voltage
Hi I am using LabView 2012, Delphi XE7 and GPIB (I think 488.2), Win7 SP1 and Agilent 53131A.
I used the given NI examples.
NI Labview example - Found in LabVIEW's help - GPIB.vi.
I tried writing and reading to query frequencies from 2 channels and they are successful.
They are are sent and read in succession.
*IDN?
:FUNC 'FREQ 1'
:READ:FREQ?
If they are successful, that meant GPIB for Agilent and NI MAX and driver are successfully installed and configured.
I am also able to use KeySight Connection Expert's to write and read, Again it is also successful.
However, When I used the given NI example in Delphi. Orginally it was saved as Delphi 3 or 4.
I used the Scope Simple example for universal counter. I used it mostly for writing and reading in the simple way. All it needs initialization, read/write and cleanup
I changed the following codes as shown below, in SimpleForm.pas
The detected device is at GPIB0::3::INSTR so, at line 32,
PRIMARY_ADDR_OF_COUNTER = 3;
String to write and read so, at line 132,
CommandBox.Text := '*IDN?';
then it was compiled with no error and run.
String to write was successfully
But upon reading, it was not successfully.
The string output is supposed to be ' HEWLETT-PACKARD,53131A,0,4806'.
The error at the end of the program is as follows below:-
Unable to read from device
ibsta = SC000 <ERR TMO>
iberr = 6 <EABO>
ibcntl = 0
From these readings, I figured out as :-
EABO means abort
I am not familiar with working of GPIB. Kindly advise.
You are correct that EABO is the identifier for an abort. In addition, we can see from ibsta = SC000 <ERR TMO> that the cause of the abort was a GPIB timeout error. I am not familiar with Keysight Connection Expert or your instrument, but since the error was from GPIB timeout, the most likely causes are:
The query was improperly formatted and the instrument thought it was just a write statement with no response needed. (That's probably why the write function had no error, but the read function timed out.)
The query was improperly formatted and the instrument returned an error.
Instrument needs to have 'Talker' capability enabled to send data. (Most instruments do this automatically with queries.)
For more information on generic GPIB commands, see this reference from the folks at National Instruments.
One of my users at a large university (with, I imagine, the aggressive security settings that university IT departments general have on their computers) is getting an empty string returned by Windows XP for CSIDL_COMMON_APPDATA or CSIDL_PERSONAL. (I'm not sure which of these is returning the empty string, because I haven't yet examined his computer to see how he's installed the software, but I'm pretty sure it's the COMMON_APPDATA...)
Has anyone encountered this or have suggestions on how to deal with this?
Here's the Delphi code I'm using to retrieve the value:
Function GetSpecialFolder( FolderID: Integer):String;
var
PIDL: PItemIDList;
Path: array[0..MAX_PATH] of Char;
begin
SHGetSpecialFolderLocation(Application.Handle, FolderID, PIDL);
SHGetPathFromIDList(PIDL, Path);
Result := Path;
end; { GetSpecialFolder }
ShowMessage(GetSpecialFolder(CSIDL_COMMON_APPDATA)); <--- This is an empty string
Edit:
Figuring out this API made me feel like I was chasing my tail - I went in circles trying to find the right call. This method and others similar to it are said to be deprecated by Microsoft (as well as by a earlier poster to this question (#TLama?) who subsequently deleted the post.) But, it seems like most of us, including me, regularly and safely ignore that status.
In my searches, I found a good answer here on SO from some time ago, including sample code for the non-deprecated way of doing this: what causes this error 'Unable to write to application file.ini'.
If you want to find out why an API call is failing you need to check the return values. That's what is missing in this code.
You need to treat each function on its own merits. Read the documentation on MSDN. In the case of SHGetSpecialFolderLocation, the return value is an HRESULT. For SHGetPathFromIDList you get back a BOOL. If that is FALSE then the call failed.
The likely culprit here is SHGetSpecialFolderLocation, the code that receives the CSIDL, but you must check for errors whenever you call Windows API functions.
Taking a look at the documentation for CSIDL we see this:
CSIDL_COMMON_APPDATA
Version 5.0. The file system directory that contains application data for all users. A typical path is C:\Documents and Settings\All
Users\Application Data. This folder is used for application data that
is not user specific. For example, an application can store a
spell-check dictionary, a database of clip art, or a log file in the
CSIDL_COMMON_APPDATA folder. This information will not roam and is
available to anyone using the computer.
If the machine has a shell version lower than 5.0, then this CSIDL value is not supported. That's the only documented failure mode for this CSIDL value. I don't think that applies to your situation, so you'll just have to see what the HRESULT status code has to say.
I am porting a C# program to Linux (using Mono). The only compatibility issues that MoMA has found were all related to printing: P/Invokes of functions from winspool.drv:
ClosePrinter
EndDocPrinter
EndPagePrinter
OpenPrinter
StartDocPrinter
StartPagePrinter
WritePrinter
These are all used in the same class, which prints files (which must be either PDF or PS) by wrapping them in PJL (to set the paper size/tray/orientation) and calling WritePrinter.
I'll need to rewrite this printing logic with non-Windows-specific code. A previous question refers to System.Drawing.Printing, but it seems to be way too low level. I don't want DrawString and DrawImage, I want "print this PostScript file". Is there functionality in Mono to do this?
I ended up using System.Diagnostics.Process to call the lp command.
What tools would you recommend for unit testing in Delphi.
I've used FastMM4 for memoryleak testing.
And MadExcept, both rule, but it doesn't help me test the logic in my programs.
I would like some alternatives, so don't all rush to suggest DUnit :-).
Any suggestions?
The most commonly used is DUnit. It's actually included in modern versions of Delphi but if your version doesn't come with it you can download it from Sourceforge.
DUnit comes with D2007.
-->File -->New -->Other
Select Unit Test from the dialogue that pops up.
There are a couple of good demo videos on it's use, I'll see if I can dig one up.
This is a pretty good one and others come up on the right:
http://www.youtube.com/watch?v=nyZnfxDqThE
You could take a look at the unit testing classes available in our SynCommons open source unit. It's used in our Open-Source framework for all regression tests. It's perhaps not the best, but it's worth taking a look at it. See http://blog.synopse.info/post/2010/07/23/Unit-Testing-light-in-Delphi
In the up-to-come 1.13 version, there is also a new logging mechanism with stack trace of any raised exception and such, just like MadExcept, using .map file content as source.
It's now used by the unit testing classes, so that any failure will create an entry in the log with the source line, and stack trace:
C:\Dev\lib\SQLite3\exe\TestSQL3.exe 0.0.0.0 (2011-04-13)
Host=Laptop User=MyName CPU=2*0-15-1027 OS=2.3=5.1.2600 Wow64=0 Freq=3579545
TSynLogTest 1.13 2011-04-13 05:40:25
20110413 05402559 fail TTestLowLevelCommon(00B31D70) Low level common: TDynArray "" stack trace 0002FE0B SynCommons.TDynArray.Init (15148) 00036736 SynCommons.Test64K (18206) 0003682F SynCommons.TTestLowLevelCommon._TDynArray (18214) 000E9C94 TestSQL3 (163)
The difference between a test suit without logging and a test suit with logging is only this:
procedure TSynTestsLogged.Failed(const msg: string; aTest: TSynTestCase);
begin
inherited;
with TestCase[fCurrentMethod] do
fLogFile.Log(sllFail,'%: % "%"',
[Ident,TestName[fCurrentMethodIndex],msg],aTest);
end;
The logging mechanism can be used to trace recursive calls. It can use an interface-based mechanism to log when you enter and leave any method:
procedure TMyDB.SQLExecute(const SQL: RawUTF8);
var ILog: ISynLog;
begin
ILog := TSynLogDB.Enter(self,'SQLExecute');
// do some stuff
ILog.Log(sllInfo,'SQL=%',[SQL]);
end; // when you leave the method, it will write the corresponding event to the log
It will be logged as such:
20110325 19325801 + MyDBUnit.TMyDB(004E11F4).SQLExecute
20110325 19325801 info SQL=SELECT * FROM Table;
20110325 19325801 - MyDBUnit.TMyDB(004E11F4).SQLExecute
Here the method name is set in the code ('SQLExecute'). But if you have an associated .map file, the logging mechanism is able to read this symbol information, and write the exact line number of the event.
Note that by default you have time and date written to the log, but it's also possible to replace this timing with high-resolution timestamps. With this, you'll be able to profile your application with data coming from the customer side, on its real computer. Via the Enter method (and its auto-Leave feature), you have all information needed for this. ;)
Like this:
0000000000000B56 + TTestCompression(00AB3570).000E6C79 SynSelfTests.TTestCompression.TestLog (376)
0000000000001785 - TTestCompression(00AB3570).000E6D09 SynSelfTests.TTestCompression.TestLog (385)
I still need to write some tool to compute the profiling, but there is already a dedicated TSynLogFile class able to read the .log file, and recognize its content.
The first time the .map file is read, a .mab file is created, and will contain all symbol information needed. You can send the .mab file with the .exe to your client, or even embed its content to the .exe. This .mab file is optimized: a .map of 927,984 bytes compresses into a 71,943 .mab file.
So this unit could be recognized as the natural child of DUnit and MadExcept wedding, in pure OpenSource. :)
Additional information is available on our forum. Feel free to ask. Feedback and feature requests are welcome! Works from Delphi 6 up to XE.