I am trying to access an USB HID device under Ubuntu(kernel-3.0). I want to write a program which could notify me whenever an USB device is attached to the bus i.e is there any event generated whenever an USB device is plugged in which I can monitor. I have looked into DBus and HAL without any success. But I don't want linux to load its current modules(USBHID and HID) when the device is plugged in. I also want to ask if the mentioned modules are also the device drivers used for HID devices.
My sole purpose is to run a script whenever an USB device is plugged into the bus which will indirectly call the above mentioned modules.
I am writing my code in C. I am quite new to linux. So it would be of great help if anyone could point me in the right direction.
Thanks..
The UDisks deamon will send the D-Bus signal "DeviceAdded" when a USB drive is inserted, and probably another "DeviceAdded" for each partition on the drive. If you have automount you would also get a "DeviceChanged" signal when the partition(s) are mounted. You can then query the UDisks interface, as well as individual devices about their properties, for example. You can find more info on the UDisks interface here: http://hal.freedesktop.org/docs/udisks/UDisks.html
One way to get more familiar with what goes on with block devices (or whatever) on D-Bus, is to install and use D-Feet to inspect the bus. UDisks appear on the System bus. You can see what is there and inspect the properties for individual devices as well as the UDisks interface itself.
Another way, which would also allow you to see what signals are transmitted on the bus, is to run dbus-monitor from the command line.
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I have a program written in Visual Basic (.NET Framework 3.0) that communicates with a power supply via a D2XX driver (over COM3) and a pump via a VCP driver (over COM2). Currently, if both USB devices are plugged in when I start the program, it tries to communicate with the pump, (COM2) when trying to communicate with the power supply (COM3). I found a temporary solution to this issue by only have the power supply connected when starting the program. Then I initialize communication with the power supply, and afterwards plug in the pump; this allows the program to communicate with both separately for the rest of the time running the program. But this process is tedious and I am hoping there is an alternative solution where I can keep both units connected via USB and the computer communicates separately. What is confusing is that this communication issue was not always the case, a week ago it worked without having to disconnect the pump (all drivers are updated, and on the device manager they are listed as their respective COM ports as well) ; I am struggling to find some correlation between what is the underlying issue.
I tried to delete other hidden additional COM ports. I made sure all drivers were updated. When the pump is communicating via the same port as the power supply, and then I try to communicate with the pump, I receive this error:
System.UnauthorizedAccessException
HResult=0x80070005
Message=Access to the port 'COM2' is denied.
Source=<Cannot evaluate the exception source>
StackTrace:
<Cannot evaluate the exception stack trace>
But again, If I start the program with only the power supply plugged in and initialize communication with the power supply, and THEN plug in the pump, this issue is evaded. I hope someone can give some sort of direction at all troubleshooting this issue because I am completely stumped. Thank you!
Most likely your program implicitly relied on the correct enumeration order. If you use devices with an FTDI product with internal flash or with dedicated eeprom, you may be lucky: Many can configured via FT_PROG to be visible only for D2XX and not as VCP. This way you can avoid the problem. Alternatively, you can try to modify your program so that it accesses D2XX first. Make sure to filter out the correct device using device informations. E.g. the serial number or the VID:PID if the device manufacturer has made the effort to aquire its own IDs. Check 3.4 FT_GetDeviceInfoList of D2XX Programmer's Guide for details.
I'm at the beginning of trying to develop a USB HID bootloader for a Kinetis processor, and getting no help from that department. I have made some modifications to Kinetis firmware designed for a similar processor(I'm using the KL26Z, the original code is for KL25Z), and I do now see the beginning of the USB enumeration(on a PC running W7). However, the PC asks for driver software, and I don't understand why, as I thought the whole point of going the HID route was that one didn't need to install drivers. So the device shows up under device manager, but as a non-working problem device. My problem is that I don't really know what should happen. Any insights would be welcome.
Here's what should happen: the computer will ask your device for its USB descriptors when it detects your device. The descriptors must have certain fields like bDeviceClass set properly to indicate that it is an HID. If the computer sees those fields, it will attach the HID driver to your device.
In the Device Manager, you should look at the "Compatible Ids" of your device. Do you see USB\Class_03 in that list? If so, that should match the driver input.inf that comes with Windows, so the INF file will be applied to your device, and you device will show up as "USB Input Device" in the Device Manager. If you don't see USB\Class_03 in your list then there is probably some problem with your device's USB descriptors or its USB stack.
I'm playing around with an old Trackball I purchased from Sparkfun. My trackball powers on, but it doesn't actually work. All the lights flash, and it indicates that I've left and right clicked, but the mouse on my screen does nothing.
I want to monitor the input values of the trackball across a USB port so I can track down the problem. I've looked for code I can run on Netbeans, but came up empty handed.
Please advise
You didn't specified what OS are you using. You need dedicated driver for this device. In case of Linux you would need to write your own driver for the kernel. But first you need to have specification of protocol which this device is using over usb and also usb protocol itself. It is quite sophisticated task to do...
In case of Windows there are some programs for dumping transmission between usb host (PC) and device (trackball), but at the moment I can't give you any name of such program. In case of Linux you can dump the transmission using tcpdump or wireshark commands.
I am working on a product with an LPC1788 which needs the following USB features:
Firmware download (from host PC to device, not through a USB
key).
File upload (from device to host).
Ideally we'd also be able to get some information from the device like serial number etc.
The device should only work with a custom Windows application, so simply using a mass-storage device as-is will not do. There are quite a lot of data to upload (200MB +), so using USB bulk transfers seem necessary to me.
What is the best way to approach this? I imagine I would need to create some sort of USB composite device(?). However, I was hoping to use nxpUSBlib or winUSB so I don't have to go through the Windows driver validation process.... What are my options? Perhaps there some way to make the mass-storage device invisible for Windows?
Thanks!
Dirk
I think you'll definitely want to go with a vendor specific bulk device and you can easily use WinUSB for all of this. This should be sufficient for everything you've specified here.
For your firmware loader I'd recommend looking at the DFU (device firmware update) specification. You'll probably want make some command for your device that when sent will cause it to reenumerate itself in to DFU mode for update (rather than a composite device that is always exposed - this restricts the issue of the other interface being in use while you're flashing your device). Then you can flash it and reset it so it will reenumerate as your vendor specific bulk device again.
I wouldn't recommend mucking with mass storage, from your requirements it will be better to implement your own protocol and create some application or DLL that consumes the WinUSB API to communicate with your device, including the firmware update.
I have a touch enabled device with WinCE, I need to show a UI whenever a USB device is inserted to the device. If there any event or method to identify the USB insertion in WinCE.
If you want to monitor just USB sticks you can use RequestDeviceNotifications for block devices.
What kind of devices can be plugged to the USB?
You can also change the USB driver code to signal an event whenever it gets an interrupt and you can wait for that event.
This website here has the exact code you need, I tested it and it works on Windows CE 6
AFAIK, you have to register a SystemState handler for a SystemProperty.
If you're using managed code and the SDF, then it's already plumbed in for you with the DeviceStatusMonitor class. This blog entry shows how to detect USB Disks, but other devices can be watched by simply changing the device class you're looking for.