retrieving detailed usb midi device information on windows xp - windows

The function midiOutGetDevCaps returns a structure MIDIOUTCAPS.
I'd need more specific information when querying a usb midi device on windows xp, in particular I'd need the information displayed under "Location" when opening the respective device using the Device Manager.
I need this information in order to programmatically distinguish between several MIDI Interfaces connected to a computer. Using midiOutGetDevCaps, I uniformly get "USB Audio Device" for every midi usb interface connected to the computer, so distinguishing between the interfaces is impossible.
To make matters worse, this string is localized, so e.g. on a German Windows you'll get "USB Audiogerät" instead of "USB Audio Device".

I guess it depends on how desperate you are. I've had my own run in with USB devices. In my case I needed to enumerate certain USB COM port related devices . . . regardless if they are currently attached to the system or not.
It is all company proprietary code, sorry I cannot post it, but the search for all information regarding USB related devices starts here (Perl):
$hostnamePrefix = "//$hostname/";
my $baseKey = "${hostnamePrefix}HKEY_LOCAL_MACHINE/System/CurrentControlSet/";
my $regVidList = Win32::TieRegistry->new("${baseKey}Enum/USB/", $optionsRef);
If memory serves me it is a reasonably straight forward structure. I believe you actually have to loop through two separate sections of the registry to get everything you need . . . if you are desperate enough to attempt this, I'm happy to answer questions where I can, but posting code would required approval from our legal department. (Not impossible, but it would take weeks to obtain.)
Also, while this will work on XP . . . I have no idea how it will work on Win7. (I don't know either way, nobody has tried it yet that I am aware of.)
Coding this was not that bad (resulting Perl Script is around 1000 lines of code which is almost 50% comments), but working out all the relationships between the keys and the special cases took several days.

Related

Detect if USB is Inserted through Application

I want to create an application or modify USB in a way so that, upon insertion into any PC, I can get the information that PC was inserted.
eg. upon insertion, I can read PC name and make an API call with this as post data so I'm able to know that my USB was inserted in some PC. But this should happen right away as USB is read by the machine, so even if the user formats it thereafter, it should not matter.
If it was earlier windows, I could write autorun and that would work. But I want this detection mechanism for Windows 7 and above.
I have done some research on the topic but could not find any reliable content. Some articles were related to USB based hacking attacks by changing wiring (USB hardware, to harm the computer) or something like that. But I totally don't want to do that. Just the detection, that USB was used.

Debugging stm32f4 via bluetooth

I'm rather unexperienced on the field of microcontrollers, I come from a Java background so the question might seem a bit noob but I didn't find much information on this.
So is it possible to debug an STM32F4 board via bluetooth (using eclipse or some othe IDE)? And if so could you send me some links that might help? We're building a robotic car controlled by a discovery board and debugging using an USB cable is not really an option if we don't want to disassemble the whole stuff every time something goes wrong. Hence this would really come in handy. So any help is appreciated
For doing this you would need to find a "Bluetooth Enabled" Debugger. I have never seen any and not sure whether there exists such thing or not.
I would suggest you one thing:
Assuming you have bluetooth connectivity between your board and your Machine,
Insert Debug strings: Send some strings from your board to your PC via Bluetooth. These strings will give you what's going on in Circuit.
For example, After Initialization, send "Init Completed" and like that. You can see these strings and see what's wrong.
I usually do this for my Wireless Device.
What you're wanting to do is really not practical; you're coming at this from way too high a level and trying to imagine the system as if it were running an operating system from the word go.
When you get the STM32 it as empty shell; you need to program it to do what you need to do and the only [sensible] way to get register-level debugging is to use a JTAG interface.
If, and this is a big if, you get it working reliably, but just want to give some debug information back while it is running, you could write a load of routines within the code to send out debugging messages when it enters certain parts of the program - and send it out over Bluetooth - but this is nothing like what you're used to single stepping through your Java code with Eclipse. If you want to do that kind of thing, you are going to have to put a little connector on that allows you to connect your JTAG or two-wire debugger cable to the processor. Even then, when you do that, you will be completely resetting your program and not simply single stepping through from where it went wrong.
You could insert a monitor program within your program to send out register values, program status etc over Bluetooth, but you still have to write the inital code and the only way to do this with out a ridiculous amount of trail and error is via your JTAG or two-wire interface.
Would this product work? It's a "IOGEAR Bluetooth Serial Adapter, GBC232A" for connecting to a serial port over bluetooth. I'm interested in wireless debugging too because my surface-clone dev computer only has one usb and this seems like it could be convenient over a tangle of usb cords and a usb hub. I have zero experience with any of this, so maybe you could validate or invalidate it as an option. I figure it just needs a proper serial connector wired up on the board and power from on-board?

Damaged files on Windows Mobile

I'm in need of help. The situation is the following:
We have a software that runs on Windows Mobile 5 and 6. It is deployed in around 15 cities on different devices (Motorola MC35, MC55, MC65, MC75, MC75A, ES400). It works perfectly fine everywhere except in one city. They have MC75A devices and every once in a while we get a helpdesk about our software disappearing from the device.
The most interesting part is when we log in to check the device, all we can see is a damaged/corrupted file system and the OS, which is set back to default.
We tried to reconstruct the problem here at our company, but we find it impossible. I'm wondering if anyone has ever bumped into this.
I'm gonna attach two images of the corrupted file system.
We use custom windows settings and AppCenter to protect the operating system from our customers. (They shouldn't be able to modify any settings on their own).
In general such corruption happens when the driver is interupted saving changes to the file system.
That can happen, for example, when a high priority thread consumes all cpu times.
It may also happen, when the device is hard reset, for example by taking the battery out during thed river is writing to the file system.
A low battery normally cannot result in that corruption:
a) as the device shuts down itslef with critcal battery power
and
b) the file system is in flash RAM (in contrast to Windows Mobile 2003 and before) and does not need battery power to hold data.
It is also possible that there is a bad behaving process doing these corruptions.
As you say you see this only in one city: What is the main difference with the devices there?
Are others also using the same device? Maybe the device series itslef or there firmware is faulty (contact symbol/motorola for new firmware or patches to the 'disk' driver)
Are the users in that area doing special things to the devices that others do not? For example remove the battery when they mean the device does not react?
Is the MC75A used in other areas and there it does not show the corruption?
You see, you have some more items to examine a rule for the corruption?

Test a embeded system (PC) from another PC

Got a customer request but no idea can it be done. So need your opinions on this. This might be a utterly stupid thing to ask but yet need some facts so can work out best solution.
Scenario,
My Customer is an OEM Manufacturer. They make an automated system with a embedded touch screen (Windows XPe) this system got a button panel with some LED indicators (apart from keyboard) and 7 USB Ports. These button panels and USB ports are checked before sending to QC process. Currently a USB thumb drive with standalone executable with all indicators and controls flags is inserted to one of the USBs and then will run the exe. This exe capture user inputs from button panel and indicate which button is pressed so that it can be verify as working. And from program user can set LED indicators to different states (flashing, steady and off) so they can be verified as well. Once this is done then USB thumb drive will be inserted to each port and will verify it recognise. But after each verify step it needs to safely remove the drive from task bar. Once each test is finish user required to fill up the sheet with all pass and fail states for the entire button panel, indicators and USB ports. This is a quite length process when its come to mass production.
Apart from this embedded system all other components which suppose to connect to one of above embedded systems are tested via a program which I make and records all test outputs as they are tested. This program installed and components are connected to a testing embedded system.
Requirement,
What customer asks, can my program test completed embedded system with our host system (testing embedded system, may be via USB to USB) Its more like Testing a PC from another PC. Any ideas ?
Additional Info.
Apart from USBs there is one Network Port.
Thanks for looking, Feel Free to ask any questions. Any opinion is appreciated.
I'm not an expert on this topic, but it seems like this would be problematic because USB is an assymetrical protocol. There are hosts and there are devices. Hosts make the requests, and devices fulfill the requests. The problem is that PCs are USB hosts, not USB devices, so you would have two hosts trying to get the guy on the other side to do what he wants. Testing with a USB thumb drive worked because the thumb drive is a device.
It sounds like the unit to be tested doesn't have an ethernet port, which is a shame, because that would be the easiest way to go. If it has a serial port you could do it that way, but that is both slow and a hassle.

Question regarding guidInstance in DirectInput library; also deals with enumeration of devices

Regarding guidInstance in DIDEVICEINSTANCE
Microsoft says:
Unique identifier for the instance of the device. An application can save the instance globally unique identifier (GUID) into a configuration file and use it at a later time. Instance GUIDs are specific to a particular computer. An instance GUID obtained from one computer is unrelated to instance GUIDs on another.
So, if I connect my device to the computer and my program does enumeration and finds the guid, do I ever have to enumerate again? Even if the user plugs and unplugs the device. If another device of the same type is plugged in, does it still recognize that the second device is not the same as the first and therefore requires a different guid? Should I just renumerate all the interfaces all the time my program runs to find my device or is once enough for a given pc?
Thanks.
I'm actually trying to solve a similar problem. According to the MSDN here, it looks like InstanceGUID is supposed to always be the same on the same computer. I've verified that if I unplug my USB device and plug it into a different port, it does indeed keep the same Instance GUID. However, if a different user logs into the same PC, DirectInput shows the same device having a different InstanceGUID!! I can't find any acknowledgement from Microsoft that this is a known problem.
So, I can partially answer your question. If you have two identical devices, you will get different InstanceGUIDs, and identical ProductGUIDs. Those InstanceGUIDs will stay consistent if you unplug your devices and move them to different USB ports. HOWEVER you will get different InstanceGUIDs if a different user logs in. At least I can verify that this is an issue on Windows 7 64bit.
The InstanceGuid will always be a unique identifier for every device plugged in - but if you remove the installation information (e.g. uninstalling a usb device) you also lose that InstanceGuid. The device will get some new unpredictable Guid when plugged in again.
The ProductGuid will always be the same for one device, since it's stored in the devices USB HID chip. It may happen though that two devices of the exact same type have the same ProductGuid. If they do, you can only identify them by their InstanceGuid (which may become invalid in some cases, as written above...).

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